Industrial Edition 2013
Issue 1, No. 1
Seawater and Industrial Outlook for Titanium “Promising”
According to TITANIUM EUROPE 2013 Experts
Industrial use of titanium products has been on the increase since that market became a significant consumer of the metal some 40 years ago. This is due, fundamentally, to titanium’s unique set of metallurgical attributes, including high strength, low density and, most important, resistance to corrosion in multiple process environments including mineral acids, organic acids and seawater at temperatures up to 130⁰ Celsius for CP alloys. Titanium plate heat exchangers, welded and seamless tubes, welded and seamless pipe, autoclaves, pressure vessels and other components are now standard in power generation, desalination, chemical processing, and many other industries. Rob Henson, Manager of Business Development for Uniti Titanium™, outlined this state of titanium in industrial applications, focusing on seawater service, as host of the Industrial Panel at Titanium Europe 2013. The recent event was sponsored by the International Titanium Association. Uniti, a joint venture of VSMPO of Russia and Allegheny Technologies Incorporated (ATI) of the US, manufactures titanium mill products for industrial, automotive and consumer markets. Prior to the forum, Henson explains the competitive advantages titanium has gained in the past two years over copper-nickel, which has been the historical workhorse material in seawater. “We’ve crossed the point where titanium is more economical that copper-nickel when strength and density are considered. Copper-nickel prices are continuing to rise, due to demand, a declining mine grade and the increasing cost of energy to produce those minerals.” Titanium, in contrast, “is very abundant in nature, and is seeing expanded global production and enhanced availability.” Titanium offers other advantages. Henson says that installed cost can be less than with copper-nickel. “Copper-nickel is half the strength of titanium and twice the density. With titanium, you can buy a much thinner wall tube because of the strength and also buy a lot less pounds because of the low density. Engineers have to make sure they design for the attributes of titanium and when they do the installed cost will be less.” In addition, because titanium is resistant to erosion corrosion, microbial influenced corrosion and crevice corrosion in seawater, “we have a demonstrated life expectancy in the power generation industry that’s proven to be 40-plus years.” Power generation is one of the largest industrial markets for titanium, followed by desalination plants, “that have been operating for more than 30 years without corrosion problems.” In fact, applications for seawater are the fastest growing industrial segment for titanium, states Henson. “It’s fair to say any process environment that uses seawater, or brackish or wastewater is an opportunity for titanium.” A potential new seawater application for the metal, in a process that can convert the temperature differential between surface and deep water into electricity, was discussed at the conference by Thierry Millot, Senior Expert Material, DCNS. The company is a French naval defense firm with a 20-year history using titanium tubes in seawater loops and heat exchangers on submarines. Millot explains that the heart of this OTEC (Ocean Thermal Energy Conversion) technology relies on a high capacity seawater/ammonia tube heat exchanger with very long tubes. “Titanium grade 2 appears as one of the best candidate materials for welded tubes considering its lower maintenance cost and longer life expectancy in a corrosive environment,” he says. Millot also outlined a longer-term DCNS project, FLEXBLUE, a civil nuclear power plant that lies on the sea bed and could supply electricity to large cities close to shore. It capitalizes on the company’s experience designing nuclear submarine heaters. He says “titanium is being considered for heat exchangers, secondary loop condensers and piping systems due to its excellent and wellknown behavior in sea water.” The use of titanium for tubes, tube sheets, castings and forgings may also be potentially significant. Stephane Pauly, Business Development Manager, Nobleclad, points out similar maintenance and lifecycle cost advantages for titanium clad steel, in which explosive welding joins a corrosion-resistant titanium alloy to lower-cost steel for pressure containment. Nobelclad, a business segment of Dynamic Materials Corporation, started as an explosion metal forming business in the late 1960s and explosion welding remains its core business today. For the mineral industry, titanium clad is used in autoclaves for pressure acid leaching of nickel and cobalt ore, as it is a more durable and reliable choice than non-metallic linings. “If you look from a long-term operating view at such equipment, because titanium clad requires no maintenance, it is a cost-effective solution,” according to Pauly. It also has proven performance records in heavy, high-pressure reactors and columns used in PTA manufacture. The third largest application for titanium clad is in heat exchangers. “Using explosives to weld, we are able to make very specialized and precise components like the tube sheets used with highly corrosive fluids,” he states. “This precision and reliability also apply to nuclear components. The nuclear industry is healthy in Europe, so that is a market where we are on the positive slope in terms of revenue.” Explosive welding can also be used to weld titanium to other metal. Where titanium is conventionally welded using TIG or MIG processes, Pauly explains, “if you want to join, say aluminum and titanium for structural applications, there are not many technologies to do that. Explosive welding is one those.” As an expert in cladding technology, Nobelclad also offers the flexibility to explosion weld metal from the size of a book to 30 square meters. For the future, Pauly says Nobelclad is “working hard on new products, new developments in the processing industry. We’re working on R&D of new, lower cost titanium grades that have not been used in the past.” Overall, the message of the industrial experts at Titanium Europe 2013 was bullish for the metal over the next decade. Economic growth, population growth and infrastructure development should drive expanded use of titanium in seawater and other industrial applications.
Titanium Industrial Business Opportunities in Global Desalination
Titanium’s superior corrosion resistance to seawater and high strength make it a material of choice for the worldwide desalination industry. As such, executives taking part in the closely watched World Industry Demand speaker panel, which addresses the annual TITANIUM Conference and Exhibition hosted by the International Titanium Association (ITA), typically identify desalination as an important global market for titanium. There are two basic technology categories for desalination systems: membrane processes (primarily reverse osmosis) and thermal distillation (evaporation). Thermal distillation is broken out into three sub categories: multi-stage flash evaporation (MSF), multiple-effect evaporation (MED), and mechanical vapor compression (MVC). Titanium finds most of its applications in the thermal distillation category, used for tubing, valves and plate heat exchangers. By contrast, titanium has only limited use in reverse osmosis systems, primarily in pump heads. Industry estimates suggest about 60 percent of desalination plants in the world use reverse osmosis technology due to its flexibility and efficiency in terms of energy consumption. Thermal distillation is the main desalination technology used in the Middle East. The world’s two largest thermal distillation desalination projects will be located in Saudi Arabia. The Ras Al-Khair MSF desalination plant, slated for completion in 2014, will require 6,000 metric tons of titanium, providing 1 million cubic meters per day (m3/day) of water to 3.5 million people in Saudi Arabia’s Riyadh region and additional 25,000 m3/day supply to Ma’aden Aluminum Complex. Thirty percent of this plant’s output will be produced by reverse osmosis. The Yanbu 3 MSF plant, slated for completion in March 2016, will supply 550,000 m3/day of water to nearly 2 million people in the industrial city of Yanbu and the nearby Medina region. Each desalination plant in Saudi Arabia will use between 5,000 and 6,000 metric tons of titanium. Doosan Heavy Industries of South Korea is the prime contractor for both projects. Executives at Valtimet, Boulogne Billancourt, France, a subsidiary of French industrial conglomerate Vallourec, say that, for the near term—except for major contracts like the two projects in Saudi Arabia—desalination is a moderate industrial growth market for titanium, with typical annual demand of around 500 metric tons. However, higher growth can be expected to ramp up in the next five to 10 years. In addition to the Middle East, Valtimet executives see opportunities for titanium unfolding in thermal desalination plants being planned in China. For thermal desalination, when MSF technology is chosen, Valtimet officials say titanium competes with copper alloys and the choice depends on the relative cost of titanium compared with copper. MSF technology is being specified for large outside-diameter (OD) tubing (above 40mm) and long tubes (above 20m). When MED technology is chosen, titanium competes with stainless steel or aluminum/brass. Tubes for MED are closer to power-generation tubes, with an OD of 25mm and length around 13m. Valtimet has several research and development projects underway for desalination applications, such as thinner titanium tubes to reduce weight and cost, as well as enhanced surface area to improve heat-exchange efficiency. Valtimet touts itself as the leading supplier of titanium welded tubes for desalination applications, with an overall annual production capacity of nearly 6,000 metric tons. It has five installations that produce titanium tubes: Morristown, TN; Les Laumes, France; Incheon, South Korea; Xian, China; and in Hyderabad, India. Leon Awerbuch, director and past president of the International Desalination Association (IDA), Topsfield, MA, said the basic goal for thermal desalination technology is to evaporate and condense seawater efficiently. Awerbuch said heat-transfer tubes are the heart of the MSF process, and that MSF plants typically offers a reliable, 40-year life span. MSF typically has an operating range of more than 110 C (230 F). Titanium is considered the material of choice for this technology in Saudi Arabia, competing against copper/nickel and aluminum/brass. As for MED, seawater is sprayed on the outside of titanium tubes and vapor is condensed inside the tube. As the name suggests, there are multiple stages of evaporation and condensation in the MED process. In MED, the feedwater preheaters and final condenser tubing are made from titanium. The operating range for MED is 65 to 75 C (150 to 170 F). In order to remain cost competitive with other metals, titanium must continue to strive for thinner-wall tubing. For MFS, titanium can reach 0.7mm for tube walls, while in MED the goal is to achieve 0.4mm. Awerbuch concurred with Valtimet’s forecast for near-term global market development, noting that China currently is evaluating MED desalination projects, which would offer growth for titanium. By contrast, Australia is a major global desalination market, but most plants there—such as Victorian Desalination Plant on the Bass Coast—use reverse osmosis technology, which favors the use of high-grade stainless steel. “Hybrid” desalination is a trend that has emerged in recent years, where a facility installs thermal and reverse osmosis/membrane technologies (a 70/30 mix), which provides cost flexibility for the operator, according to Awerbuch. All thermal desalination plants are combined with power plants when exhaust steam from the turbine is the source of energy for desalination. Another potentially lucrative business trend for applications in the United States involves redeploying thermal desalination technology for burgeoning hydraulic “fracking” (injecting water and chemicals deep underground) to extract natural gas from underground shale deposits. While fracking offers the promise of producing high volumes of natural gas to meet ever-increasing energy demands, the process has garnered its share of criticism regarding environmental issues. In particular, a major environmental concern is the disposal of “flowback” water produced after underground injection, which has a higher salt content than seawater. As a result, proper disposal of this flowback water is problematic. Thermal desalination can be used to clean up the flowback water, allowing it to be reused for another fracking project. Awerbuch said this would create a new market for desalination technology. “In my opinion, titanium would clearly be the material of choice for this application,” he said. In addition to MED and MSF, MVC desalination is a candidate for this application. Water vapor is compressed and passed over a heat exchanger condenser, and the resulting water is stored for reuse. According to information posted on its Web site (www.idadesal.org), the IDA, a non-profit organization, describes itself as the world’s leading resource for information and professional development for the global desalination industry.
Titanium in Medicine:
A Look Forward in Alloys, Manufacturing and Distribution
Over the past 50 years, titanium has achieved an impressive record of success in a range of medical products and applications used to improve and extend people’s lives. Mechanical characteristics that have driven it to become the metal of choice in medicine include high strength-to-weight ratio, low modulus, corrosion immunity, low risk of allergic reaction and biocompatibility. Today, the metal and its alloys are used extensively in total joint replacements, dental implants, orthopedic and trauma devices, prosthetics and surgical instruments. However, the relatively long history of alloy and manufacturing innovations that enabled creation of these multiple product forms now raises the question of what future advances might still be realized and what direction they will take. Hans Schmotzer, of SigmaRC, a technical expert and management consultant in medical new product development, observes, “You have to admit if you look at these fields – devices, hardware products – from a general market and also an investor financial perspective, the market in the developed countries is in a very, very mature state. “Senior executives in many of the device companies have basically cut R&D spending because they say there’s not much to gain in the foreseeable future with traditional device innovation,” he continues. Schmotzer is one of three experts who weighed in on the outlook for medical titanium during Titanium Europe 2013, sponsored by the International Titanium Association in March, 2013. Francisco Faoro, of Institut Straumann AG, a leading manufacturer of dental products targeted to premium markets, points out that alloy research and development, on the other hand, remains strong, at least at his firm. The focus remains on titanium, he explains, because biocompatibility and osseointegration requirements limit the selection of materials. “Roxolid™, our new titanium/zirconium implant alloy, took many years to develop, but at the end we have a superior material which has both higher strength and the topography for excellent osseointegration. It’s a combination nobody else has.” Roxolid™ is formulated for small diameter implants in narrow interdental spaces where the tooth must endure high chewing forces. A leading titanium distributor, Andre Hempel, of Hempel Special Metals, sees changes coming in the specifications required for materials used in manufacturing devices and implants. “What is going to change might be tolerances, surfaces, mainly because of equipment that’s changed. Machinery may require tighter tolerances for automation.” Mergers, especially within a segment, can also lead to feedstock specification modifications, such as in bar lengths used in different manufacturing methods for the same product. Both situations may require additional work at the service center that may influence prices. “You have to take every single piece and put it into a machine. Is it worth the effort? I can’t answer that… I’m not an implant producer.” Schmotzer says he anticipates “development taking place more in manufacturing technology.” Today, he says, some 80% to 90% of products are still machined from stock, as they have been for 40 years. “I see the manufacturing landscape making evolutionary changes to move to powder-based materials. “With the development of rapid prototyping and injection molding technologies, I think powder metallurgy is becoming more and more the focus area,” Schmotzer continues. “You are still producing the same devices, but from powder rather than stock. These are simple processes that generate less material waste and allow designs you can’t manufacture cost-effectively from solid material.” The new powder manufacturing processes also enable creation of custom shapes, fueling a trend toward individualized medicine, according to Schmotzer. “Dental is already highly patient specific and similar trends are taking place, while not to the same degree, in orthopedics.” Additive processes like laser and EB sintering allow greater manufacturing flexibility and hollow or porous structures for example. Metal injection molding can achieve more complex shapes. Hempel says the next generation of medical titanium product improvements may also require cutting or processing standard mill product materials to specific shapes or profiles. “What we see is innovation comes from design of the product, not chemical composition. Design impacts the shape the OEM needs. They come to us, we go to the mill. Can we provide the profile at a competitive price? We are the go-between, especially if the mill is in the U.S. and the OEM is here in Europe.” This critical role of the distributor as the mill-OEM go-between reinforces another recent trend Hempel observes for the future: OEMs concentrating their business with fewer distributors, to increase their volumes, control their prices and receive complementary service. Faoro sees additional future application potential in Straumann’s Roxolid™. “It could be used in fracture care and orthopedics, such as hip or knee replacement. Roxolid™ is biocompatible and has such excellent in-growth capabilities, that it might have potential everywhere this behavior is required.” Beyond powder technologies, Schmotzer looks for promise in products that separate themselves as unique. For example, he says, titanium has many positive aspects and a single significant drawback: “That is low wear resistance. Wear produces particles with a negative biologic response. Today, processes like anodizing have resolved some of the issues, but if technologies were available that could eliminate the particles, it would open up new applications for titanium.” “But is that realistic?” he continues. “In some applications you have to live with the limitations. But it would certainly lead to product differentiation. And in a mature market, if you can’t drive fundamental innovation, you need to drive a differentiation campaign by delivering added benefits.” The representatives of all three medical titanium supplier segments – Francisco Faoro addressing alloy research and development, Andre Hempel speaking about mill product distribution and Hans Schmotzer discussing device manufacturing – expressed optimism regarding the titanium industry’s role in medicine today and in the future, while acknowledging they must recognize the trends in each of their respective customer bases to enjoy continued success.
Advances in Technologies and Market Opportunities
Presented at TITANIUM EUROPE 2013
Speakers representing a manufacturer of vehicle exhaust systems, a producer of investment castings and a university research department offered expert insights into emerging uses and potential opportunities for titanium during the recent Titanium Europe 2013 conference. The Emerging Markets panelists also examined their companies’ technologies and anticipated contributions to future growth in use of the metal. The event was sponsored by the International Titanium Association in Hamburg, Germany. Titanium today is a staple in widespread markets, of course. In aerospace it is essential for engines and airframes, in both commercial and military planes. It is also used throughout industry – in power generation, chemical processing, oil and gas production and in marine environments – as well as in medicine. The versatility of titanium and its alloys is due to its unique combination of metallurgical characteristics, including a high strength-to-weight ratio, natural corrosion resistance and low modulus. These attributes make it well-suited for use in automotive and motorcycle exhaust systems as well, explains Jaka Klemenc, Head of Research and Testing for Akrapovič, d.d. “Akrapovič is a specialized company that’s unique in the world.” he says. “No one else puts titanium into so many exhaust systems.” He further notes the firm’s design and fabrication expertise. “Compared to high-volume exhaust manufacturers, Akrapovič has strong technology for forming – the benefit of years of experience.” Klemenc’s panel presentation examined testing methodologies for comparing exhaust systems of titanium and stainless steel using the same system configuration, vehicle and load/riding conditions. The titanium exhaust offers a weight benefit of 40 – 45% over stainless steel, which impacts both absolute mass and dynamic mass, felt in handling and drivability. Titanium’s benefits in vibration, sound quality and heat transfer were measured and best overall performance was observed. Titanium is particularly attractive for performance cars, where the advantages outweigh the cost. “For these cars, both in the OEM business and aftermarket, weight reduction is key. For sports cars it affects the whole dynamics of the vehicle and the fuel efficiency. Titanium alloys provide a good price/performance ratio,” Klemenc summarizes, “meaning it may cost more, but because of its positive attributes, it is worth choosing.” Automotive applications were an appropriate topic for a conference in Germany, given the region’s contributions to high-end cars and motorsports. Sarah Mott, Precision Castparts, a manufacturer of investment castings, acknowledges that. “We actually do some work in Formula One racing,” she says, before concentrating on the military applications more typcial for her firm. “It’s interesting how different the work is between the civilian side of vehicle manufacture and the defense side.” Precision Castparts is currently “seeing a lot of interest from defense contractors in titanium investment castings” for combat vehicles, artillery systems and aerospace components, according to Mott. “Over the past decades, we’ve seen the symmetry of the battlefield start to change. Modern military equipment needs to be very agile and easy to reposition. Titanium investment casting offers a lighter, stronger solution that tends to use less material and sometimes less labor, so it can be cheaper,” compared to traditional fabrication. “Vehicles use less fuel and it takes less fuel to fly that equipment into theater, which is a big bonus these days.” The firm’s capacity to cast large sizes – up to 100” in length, 70” in diameter and 1700lb pour weight –gives it a competitive advantage. “We’re seeing a lot more orders for parts like drive train components for military trucks,” she says. Unmanned aerial vehicles (UAV) represent another opportunity. Now that the systems are proven, the military is adding functionality which requires reduced weight and stronger landing gear. “Titanium and investment casting tend to do very well for manufacturers.” Another technology that holds promise for expanding titanium’s utility, anodic oxidation, was the conference focus of Dr. MariaPia Pedeferri, Associate Professor at Politecnico di Milano. The process thickens titanium’s spontaneously occurring oxide film, which is responsible for its natural corrosion immunity, to make the metal more suitable for certain biomedical and mechanical applications. (Photos, page 16.) “This is an electrochemical technique but a quite simple one,” states Pedeferri. “Put a piece of titanium and a piece of another metal, any metal, in an acid solution – it can even be Coca-Cola®. Then connect each piece to a pole of an electrical source. Depending on the voltage difference you obtain a very different film on the titanium surface.” Higher voltage results in thicker film and different surface properties, including color. The thicker film improves the mechanical surface properties of the metal, increasing wear resistance. “In screws and nuts, you might have problems tightening them down more than a few times before friction damages the surface. Anodizing can increase the service life of the screw.” Pedeferri cites biomedical and industrial applications for anodizing. “For hip joints, where you have problems of friction, fretting, there are commercialized treatments. Anywhere you have very severe conditions and mechanical loads, the treatment can be exploited.” In the future, she sees growing architectural use of anodized titanium, as the treatment “adds aesthetic value and can promote the degradation of pollutants.” The surface colorization contributes to its surging popularity in jewelry, as well. For Castparts, Mott says future growth could result, in part, from UAVs in commercial use. “A potential civilian market could be particularly exciting for us. From our understanding, the US may lift airspace restrictions on using UAVs for law enforcement; for agricultural fertilizing; even for insurance estimating.” In the automotive sector outlook, Klemenc “really sees high-performance cars, where weight matters, as the niche for Akrapovič. Our next challenge will be getting into other parts and using our titanium technology in other segments. We have a foundry, casting, so we can be looking at some structural parts, engine parts. It’s a matter of what people are willing to pay.” Every emerging application for titanium will be subject to the cost/benefit analysis. Pedeferri concludes, “In, say jewelry, titanium is ‘exotic’ so cost is not a problem. In standard applications, screws and nuts for a car, cost can be a problem. So there is a strange perception of titanium. But communication plays an important role. If people understand increased performance, or spending less over a lifespan, they can see that titanium can pay for itself.”
Executive Summary: TITANIUM 2012 Conference
World Industry Demand Trends Frank L. Perryman, president and chief executive officer, Perryman Co., Houston, PA, served as the moderator for the World Industry Demand Trends panel, which typically is the “must-see” presentation at the annual titanium conference. Dawne S. Hickton, vice chairman, chief executive officer, and president of RTI International Metals, Pittsburgh, reviewed forecasts in commercial aerospace. Citing statistics from a Boeing market outlook (2012-2031), its expected aerospace carriers will be retiring significant portions of their fleets during the next 29 years. Hickton’s presentation indicated that the aerospace carriers will need 34,000 new airplanes of which 41 percent will replace older, less fuel-efficient aircraft, while 59 percent of the deliveries will reflect the growth in emerging markets. The two trends driving the need for new aircraft, as identified in Hickton’s remarks, reflect current market dynamics and concerns expressed by the global aerospace sector. Airlines, in recent years, have felt the pinch of higher fuel prices and have put a premium on jets that provide enhanced fuel efficiency, in order to reduce operational costs. A reduction in fuel consumption will be achieved by new generations of high-efficiency jet engines and a reduction in aircraft weight; two solutions that favor the continued use of titanium alloys. Fleet age, especially among North American carriers, is also driving the need to purchase new commercial jets. Citing numbers from Airline Monitor, Hickton said American and Delta have a significant percentage of their fleets that are 20 years and older—44 percent for American and 39 percent for Delta. As for growth in emerging aerospace markets, once again this is a factor that calls for titanium components used in the new generations of long-distance aircraft. These new markets, inspired by the growth of the global economy, reflect the growing demand for expanded business and pleasure travel to destinations in China, Brazil, India and South America. Hickton’s presentation also raised questions concerning the use of titanium in commercial aerospace. She identified aluminum lithium alloys, near-net-shape materials and composites as potential competitive threats to challenge titanium as a material of choice for aerospace components. For the aerospace industry, she said questions remain whether there will sufficient future financing and access to capital markets to support the near-term business plans of global carriers, a concern that involves the ongoing, lackluster economic environments in the Euro Zone and the United States. In addition, referring to an RTI study, she said there should be a continued consolidation trend in the aerospace supply chain for the delivery of titanium. Recent examples of this consolidation include Allegheny Technologies Inc.’s acquisition of forging and investment casting manufacturer Ladish Co. Inc., and RTI’s purchase of Remmele Engineering Inc., a company that specialized in precision machining of titanium. Joining Hickton on the World Industry Demand Trends stage were other leading titanium industry executives. James M. Buch, executive vice president, commercial, Titanium Metals Corp. (TIMET), Dallas, examined titanium demand for aerospace engines. Buch said that, despite some program delays, which may impact near-term shipments, engine backlogs remain strong and large high-bypass turbofans will continue to spur titanium demand, at least through 2018. Michael G. Metz, president, VSMPO Tirus US, Highlands Ranch, CO, delivered an overview of demand for titanium in the Russian Federation. Metz said that total Russian demand for titanium, estimated at 7,000 metric tons in 2010, will grow to just over 12,000 metric tons in 2014 and nearly 14,000 metric tons by 2017. Aerospace, including engines, airframes and rocket manufacturing, consumes about 60 percent of the titanium produced in the Russia. Other major application areas include general industry, shipbuilding and power generation. Zou Wuzhuang, the board chairman of Baoji Titanium Industry Co. Ltd. and the chairman of the China Titanium Association, provided an outlook for the titanium industry in China. Wuzhuang indicated that, for the first half of 2012, the output for titanium mill products in China reached 28,000 metric tons, which represents an 8-percent increase compared to the same period in 2011. Plate and sheet represents nearly half of the mill products total for the first six months of 2012, followed by bar and forging products (34 percent) and pipe and tube (nearly 15 percent). Meanwhile, titanium sponge output in China registered 32,000 metric tons for the first half of 2012, nearly 9 percent below the comparable 2011 period. Wuzhuang cited a decline in global sponge prices as the main reason behind the decrease in Chinese sponge output. Shozo Nishizawa, chairman of the Japan Titanium Society, offered his outlook for Japan’s titanium industry. Nishizawa said Japanese mill shipments for the first half of 2012 totaled 10,000 metric tons, compared with just under 20,000 metric tons for all of 2011. Japan’s sponge production capacity, as of February 2012, registered nearly 70,000 metric tons. The sponge production in Japan in 2010 was just above 50,000 metric tons. Gilles Dussart, chief operating officer, VALTIMET, Boulogne, France, discussed key drivers of titanium consumption in industrial markets such as power generation and desalination markets. For 2012, titanium demand for global industrial markets will reach 22,500 metric tons. Dussart said demand is expected to exceed 25,000 metric tons in 2013 and reach 30,000 metric tons by 2017. Richard J. Harshman, chairman, president and chief executive officer, Allegheny Technologies Inc., Pittsburgh, discussed titanium applications for military aircraft, along with land-based and sea vehicles, which will continue to impact future titanium demand. World Industry Supply Trends Titanium Metals Corp. (TIMET), Dallas, sponsored World Industry Supply Trends speaker panel, which was moderated by Henry Seiner, TIMET vice president, planning and materials, highlighted trends in sponge and scrap, as well as the status of key industrial metals used for titanium alloys. Seiner’s presentation, “A Melter’s Perspective on Developments in Raw Materials,” noted that the titanium scrap and sponge markets have “disconnected.” A 10-year review of the titanium scrap market shows “extreme volatility,” he said. A slide in his presentation stated “scrap was extremely attractive in 2009; sponge become more desirable during 2010-2011; and scrap is again attractive in 2012.” “A year ago, this panel heard about tightness in the feedstock ore markets,” Seiner stated in his preview notes prior to his presentation at the conference. “This phenomena unfolded as expected during late 2011 and early 2012. But the scrap market of late 2011 and thus far in 2012 has been much weaker than most market participants expected.” Using history as a guide, he anticipated future volatility for scrap and sponge, with the possibility of periodic shortages for global supplies. Jeff Carpenter, senior manager, raw material procurement/supplier management for Boeing Commercial Airplanes, shared Boeing’s views on recycling titanium scrap. The aerospace manufacturer, he said, is implementing a “scrap-revert” strategy with suppliers. The mission, he said, is to create a steady, closed-loop stream of segregated titanium from its supply base and internal Boeing sources. “No scrap left behind” and “all scrap segregated and treated like gold” are among the guiding principles of the initiative. For Boeing, the benefits of the program include the ability to keep aerospace scrap in the aerospace market while stabilizing the lead time, cost and market fluctuations of titanium. In addition, the scrap-revert strategy will help ensure a reliable supply of raw material for titanium mills. There were just 20 participants when Boeing launched the program in 2009. Carpenter said it’s expected there will be more than 200 companies involved in the scrap-revert program by 2014. Dr. Nagesh Chaganti, who heads the Titanium and Magnesium Group of Defence Metallurgical Research Laboratory (DMRL) in Hyderabad, India, was not in attendance at this year’s event but Mr. Seiner offered Dr. Chaganti’s presentation reporting on the nascent commercial production of titanium sponge. According to Chaganti, India possesses large reserves of ilmenite, which is rich in TiO2 content, located along its southern peninsular coasts. India has the capability for ingot melting and the production of titanium alloy mill products, but has had a gap in the titanium “ore-to-product” cycle—namely, titanium sponge production. Chaganti said India traditionally has not had a widespread appreciation for the long-term benefits of industrial titanium applications, due in part to sharp fluctuations in prices and uncertain international supplies of material. As a result, DMRL, through the development of Kroll process of magnesium reduction of titanium tetrachloride, has established India’s first commercial titanium sponge plant (a capacity of 500 metric tons per year) at KMML, Kerala, a facility that was commissioned in February 2011. Because of this new sponge capability, India stands ready to increase its usage of titanium in a wide range of industries, according to Chaganti. Terrance T. Perles, president of TTP Squared Inc. and MoTiV Metals, LLC, outlined factors that influence the supply and demand fundamentals of the molybdenum and vanadium markets as they relate to titanium alloy production. Perles said that, while the steel industry dominates demand for molybdenum and vanadium, titanium and superalloy production accounts for 3 and 4 percent, respectively, of annual consumption. High-purity oxides of molybdenum and vanadium are consumed by titanium and superalloys as master alloys that carry stringent quality requirements. Even though titanium is a minor consumer of these oxides compared with the steel sector, Perles cautioned that, for the titanium industry, the master-alloy supply chain is fragile, with a limited number of qualified producers and oxides. TTP Squared Inc. is a consulting firm serving producers and consumers of vanadium, while MoTiV Metals is a North American sales agent from metals producers. Perles established the two companies in 2010 and both are based in Pittsburgh. He previously held executive positions at vanadium producer Stratcor. According to an online news report dated March 30, citing data from the U.S. Geological Survey, China is the world's largest producer and consumer of molybdenum. A separate online article stated the vast majority of the world’s vanadium comes from three countries: China, Russia and South Africa. Vanadium enhances titanium’s superior strength-to-weight ratio, a critical property in aerospace applications. Jacko Preyser, general manager, sales and marketing for global mining giant Rio Tinto Iron and Titanium (RTIT), discussed the titanium feedstock market. Preyser pointed out that RTIT is the world’s largest producer of high-grade feedstock, such as rutile, which is preferred by producers of titanium sponge. He estimated RTIT commands a 50-percent share of high-grade feedstock sales. As China and emerging economies continue to drive the growth of titanium consumption, demand is expected to outstrip current levels of feedstock—both online supply and committed projects—by 2014, according to Preyser. As a result, he warned that, due to this projected supply/demand “inflection point,” there is an urgent need to develop new sources of feedstock for the titanium industry. Distinguished Guest Speakers Michael L. Warner, director, market analysis, Boeing Commercial Airplanes, Seattle; Eric Zanin, the senior vice president and head of materials and detail parts procurement for European aerospace giant Airbus; and Benoît Brossoit, senior vice president, global operations, United Technologies Corp. (UTC), Hartford, CT, served as the three distinguished guest speakers at TITANIUM 2012. VSMPO AVISMA sponsored Warner’s presentation. He concurred with information in Hickton’s presentation, saying 34,000 airplanes will be needed during the next 29 years to replace the aging commercial airline fleets, representing a value of $4.5 trillion. He pointed out that, of the overall total, single-aisle jets are the largest category to be ordered—23,240 aircraft. However, in terms of dollar value, single-aisle and twin-aisle aircraft will be about equal—just over $2 trillion each. As for Boeing’s business, he described the 777 as “the preferred choice,” with 1,379 “firm orders” and 1,039 deliveries to 63 customers. Regarding business so far this year, Warner said Boeing had 719 net orders through Sept. 25. There were 380 deliveries through the end of August, with a backlog of 4,057 aircraft. Titanium is the material of choice for precision jet engine components; structural assemblies in the airframe and landing systems; forged-wing structures; fasteners, springs and hydraulic tubing; and engine nacelles. In addition to the 777, Boeing’s 787 Dreamliner, as well as Airbus’ A350 and A380, scheduled to be commercially unveiled in 2013-14, all have significant utilization of titanium. Warner said Boeing sees a “weak” economic outlook through 2013, with most of the global growth being spurred by the emerging economies. The European Union’s mounting sovereign debt, the tepid economic environment in the United States, volatile jet-fuel prices, and concerns regarding Iran, all stack up as question marks likely to affect the global economy in the near term. Despite the overall economic uncertainty, Warner called upon the titanium industry to remain competitive to garner aerospace applications. “Both near-term and long-term, we see a strong and growing aviation market,” Warner said. “Airline traffic is forecasted to grow at a 5-percent annual rate over the long term, with cargo traffic projected to grow at 5.2 percent per year.” Zanin, whose presentation was sponsored by RTI International Metals, Inc., agreed with Warner’s positive outlook for commercial aerospace, saying air traffic would double during the next 15 years. As of Aug. 31, Airbus had “firm orders” of 11,863 jets and a “firm” backlog of nearly 4,460 aircraft. The “intelligent airframes” of the Airbus A350 and A380 will continue to see increased utilization of titanium for landing gear, pylons, door frames and other critical components. Titanium will account for 14 percent of the A350 and 6 percent of the A380. TIMET sponsored the talk by Brossoit, who earlier this year was named UTC vice president of operations. According to bar charts shown during his presentation, he said UTC Aerospace would double its demand for titanium by 2020, compared with 2010. It would secure capacity through long-term agreements and building partnerships with qualified suppliers, as well as supporting the global supply chain structure. Renewable Energy Paul Gipe, author, advocate and renewable energy industry analyst, outlined renewable energy initiatives that have the potential to create business opportunities in the international titanium industry. The over-arching thrust of Gipe’s presentation (“Renewable Revolution—How Renewable Energy is Remaking Electricity Generation”): that the renewable energy “revolution” is well underway and being demonstrated as a reliable, real-world solution to produce electricity, especially in Europe and Asia. For titanium, “select,” potential business opportunities worth exploring would include components for wind turbines as well as geothermal and biomass energy generating systems. Given its inherent properties of high strength, light weight and corrosion resistance, titanium would be a contender to retrofit existing energy-generating systems or be specified as a material of choice on new systems. Gipe promoted the idea of a mixture of renewable systems—a combination of solar panels and wind turbines—as the best approach to provide energy for a given region or community. He attempted to dispel several “myths” attached to renewable energy technology. Gipe pointed out that renewable energy is not “cheap,” in terms of development costs or up-front capital investment; however, it is affordable and worth being considered as a solution for generating power. In addition, he said renewable systems can be scaled up and brought online relatively quickly, compared with the typical timeframe needed to complete a traditional power-generating plant. Trends that define the renewable energy revolution, according to Gipe, involve smaller, more localized ownership, storage, distribution and consumption of power. Interviewed prior to TITANIUM 2012, Gipe strongly underlined the point that renewable energy is now a viable technology that must be evaluated on a commercial scale; that the current revolution has moved well beyond a research phase. “I’ve been saying it for years: it’s no longer a question of research; it’s about doing it,” Gipe declared. “That’s what countries in Europe and Asia have decided in terms of a developing a comprehensive energy policy. We know how the technologies work. Today it’s about ‘learning by doing’ on a commercial scale.” For example, Gipe said Denmark currently supplies 20 percent of its electricity with wind energy, while Germany—the world’s fourth-largest industrial economy—provides 20 percent of its electricity from a mix of renewables. By contrast, the United States has been relatively slow to embrace the renewable energy revolution, according to Gipe. Gipe is a former acting executive director of the Ontario Sustainable Energy Association and executive director of the Kern Wind Energy Association. Safety First Greg Creswell, regional safety manager, Titanium Metals Corp. (TIMET), Dallas, and the chair of the ITA’s Safety Committee, was the moderator for a panel on titanium safety and fire prevention, a session sponsored by the ITA’s Safety Committee. A certified safety professional and principal member of the National Fire Protection Association’s (NFPA) 484 technical committee on combustible metals, Creswell also delivered a paper on titanium dust hazards. He reviewed the NFPA 484 standard and offered a timeline to define a dust explosion event in an industrial production facility. The safe handling and storage of titanium—a reactive metal that will burn—begins with good housekeeping and extends to plant maintenance and plant-wide safety procedures. For titanium, Creswell said the conditions for an explosion include the following points: metal dust must be fine enough to be airborne; a dust cloud must be at the “minimum explosive concentration”; there must be sufficient oxygen present to support and sustain combustion; there must a source of ignition; and the metal dust must be dry and confined. René Cooper, technical sales specialist, International Titanium Powder, Ottawa, IL, reviewed his company’s creation of titanium powder handling guidelines. Cooper’s presentation reviewed the requirements for fire and explosion hazards, proper storage of powder, and safe handling precautions. Rick Mason, director of safety, environmental and corporate quality at RTI International Metals Inc., addressed “Key Elements of RTI’s Safety and Environmental Management System.” Mason reviewed his work to develop a safety and environmental management system, based on the principles of ISO 14001, Environmental Management Systems. Andrew M. Allen, president and chief executive officer of GSL Inc., Tulsa, OK, discussed new developments in titanium safety, handling and processing, highlighting his company’s Firebane technology, an aqueous fire extinguishing agent. He described Firebane as a non-toxic, biodegradable product approved by the U.S. Environmental Protection Agency. Military/Defense Gus Gustin, TIMET sales director, military ground systems and marine, served as the moderator for the Military/Defense speaker panel, sponsored by TIMET. John Monsees, owner and chief executive officer of Reactive Metals Group LLC, a consulting firm in San Diego, examined new methods for promoting titanium to be specified in military and defense contracts. Monsees presented ideas on the best ways for titanium companies to work with military contractors. He noted that, in order to execute a “successful sell,” titanium companies must ensure the customer’s part design and manufacturing process is properly designed to accommodate titanium and fully exploit the metal’s properties. The advice from Monsees is to teach customers how to design with titanium, helping them to understand how to avoid cost. “Do not abandon them to their own utilization of titanium,” he said. “Just a few questions along the way can short circuit potential problems.” William A. Gooch Jr., president, WA Gooch Consulting Inc., Saint Petersburg, FL., considered “New Processing and Fabrication Technologies for Current and Potential Titanium Military Applications.” For applications such as tank armor, Gooch referred to technical papers describing the ballistic advantages of wrought titanium plate compared with steel wrought plate. Gooch identified new processing and fabrication technologies for both armor and non-armor applications to expand the use of titanium alloys on military ground platforms. In particular, he noted manufacturing technologies to “process low-cost titanium powders into fully consolidated near-net shape components for military applications.” He said the capability to form complex shapes from low-cost powders would allow for the application of lower weight and lower cost titanium parts for military systems. Aerospace Opportunities Speakers in two panels—Commercial Aerospace and Aerospace Materials and Processes—focused their attention on titanium applications and manufacturing techniques in the high-flying global business sector. Jeff Masingill, vice president, sales and marketing, RTI Remmele Engineering Inc., New Brighton, MN, was the moderator for the for the Commercial Aerospace panel, sponsored by RTI. Interviewed earlier this year, Masingill said that, considering the accelerating demands from commercial aerospace customers, titanium innovation is required to meet the challenge. “As commercial and aero-engine market conditions evolve, there is a greater need for higher-performing titanium alloys, which can withstand the rigors of more demanding environments,” he said. Addressing the topic from a supply-chain perspective, Maryse Ingenito, director, global strategic sourcing, United Technologies Corp., said aerospace’s “buy weight” raw material demand for titanium will reach 225 million pounds by 2020, compared with the current level of more than 100 million pounds. By comparison, demand for superalloys and composites will be around 125 million pounds by 2020, while demand for aluminum (including aluminum-lithium alloys) will reach 650 million pounds. Ernie M. Crist, director of process and product development at RTI International Metals, discussed the potential benefits of lower-temperature superplastic forming (SPF) and his company’s progress on recent production-scale SPF trials for titanium 6/4 sheet at 1425-1475 F (774-800 C) and pilot-scale work for Ti 6242 at 1550 F (843 C). Dr. Yoji Kosaka, senior manager, U.S. research, at TIMET’s Henderson Technical Laboratory, Henderson NV, moderated the Aerospace Materials and Processes panel, sponsored by TIMET. Dr. Daniel G. Sanders, senior technical fellow, Boeing Research and Technology, reviewed titanium machining and joining techniques that could help reduce cost in aerospace applications. In his summary, Sanders said progress in welding and joining methods, such as laser (fusion) welding, linear-friction welding, friction-stir welding are “revolutionizing” the use of titanium for aerospace applications. He also pointed to advances in large-part SPF as benefiting from these joining/welding technologies. Dr. Daira Legzdina, principal product design engineer at Phoenix-based Honeywell Aerospace, and Eric J. Fodran, Ph.D., materials and process engineer for Northrop Grumman Aerospace Systems, presented separate papers on additive manufacturing in titanium alloys. Legzdina, reciting the ASTM definition, described additive manufacturing (AM) as a process of joining melted materials to make objects from 3D model data, usually layer by layer. AM, she said, can be a “game-changing” technology for complex parts that are difficult to machine. She identified direct-metal laser sintering, ion fusion formation and electron beam melting as three AM technologies gaining acceptance and being explored on a global basis. These techniques have the potential to provide cost savings in the aerospace industry, offering the ability to produce prototypes quickly and inexpensively. A separate panel group, Welding and Allied Technologies, continued the conversation on joining technologies. EWI, Columbus, OH, sponsored the panel, which was moderated by Brian Bishop, EWI Aerospace, business development manager. Mike Eff, EWI project engineer, presented a paper on “Novel Technologies for Similar and Dissimilar Titanium Joints.” Eff discussed two novel joining technologies: friction stir welding; and electro spark deposition (ESD) welding. Powder Presentations There were three panel groups dedicated to titanium powder: Powder Metallurgy, moderated by Georg Abaskumov, director of business development to ADMA Products Inc., Hudson, OH; Powder Production, moderated by Colin McCracken, technical director of Ametek/Reading Alloys, Robesonia, PA; and Manufacturing Power Parts, moderated by Stanley Seagle, industry consultant and retired vice president of technology at RMI Titanium Co. Katsuyoshi Kondoh, vice director for the Joining and Welding Research Institute, Osaka University, Japan, offered thoughts on “Next-Generation Development of a Superior Grade Titanium (Ti-6Al-4V) Alloy Via Oxygen Solid Solution Strengthening for Aerospace and Defense Applications.” Tyrone Jones of the U.S. Army Research Laboratory, APG, MD, was credited as a co-author of the technical paper. Kondoh reported the powder metallurgy process provides opportunities to reduce the cost of materials and improve mechanical performance of titanium and related alloys. He said powder metal titanium using titanium hydride (TiH2) powders demonstrated high strength and ductility. Carbon, nitrogen and oxygen were effective in creating a good balance between tensile strength and elongation at ambient temperature. However, an oxygen solid solution strengthening effect for powder metal Ti-64 is not enough for significant improvement of ballistic performance, according to Kondoh. McCracken reported on the launch this year of Ametek/Reading Alloys new powder metallurgy: plasma spheroidized (PS), which he described as a high-volume batch process. The company has been producing hydride-dehydride (HDH) powders since 2001. HDH powders are characterized by their blocky, angular morphology and are suited for press/sinter, roll compaction and plasma spraying techniques. The HDH titanium powder is fed into an induction-coupled plasma field that melts and “spheroidizes” the powder. The resulting PS powder morphology is similar to plasma rotation electrode process (PREP) powder—free from agglomerates that eliminate argon gas entrapment. The PS powder process produces a full range of particle size distribution (PSD), from coarse to fine. ADMA, which sponsored the Powder Metallurgy speaker panel, is a diversified group of companies involved in powder metallurgy products, such as titanium and other advanced materials, which target industrial, aerospace and military applications. Advanced Manufacturing Technologies Dr. Padu Ramasundaram, corporate director of technology at RTI International Metals Inc., moderated the Advanced Titanium Manufacturing speaker panel, sponsored by RTI. Dr. Adam Brown, a research associate at the Advanced Manufacturing Research Centre (AMRC) at the University of Sheffield in the UK, touted the facility’s research into next-generation titanium machining strategies. As described on its Web site, the AMRC, a “factory of the future,” is composed of more than 60 key players in global aerospace and advanced manufacturing, including Boeing, Rolls-Royce, BAE Systems, Messier Dowty, Sandvik Coromant and Renishaw. Working with students in the university’s Department of Mechanical Engineering, the center spans a spectrum of manufacturing technologies and processes, from materials suppliers to assembly specialists. Brown provided a snapshot of metalworking equipment at the center and mentioned some of the programs being explored to advance titanium manufacturing techniques. For example, he listed some of the inherent limitations when machining titanium, such as high cutting forces, poor tool life and “chatter,” which he defined as a “self-excited vibration” that limits productivity and tool life. The center seeks to overcome these challenges through its research to understand the underlying causes of chatter, then identify methods to eliminate it while optimizing tool wear and CNC tool paths and cutting parameters to boost productivity. He cited one recent case-study research program at the center that achieved a 50-percent reduction in cycle time and corresponding increase in productivity on a Rolls-Royce machining process for a family of titanium and nickel alloy jet engine fan disks. Two separate panels: Industrial Session speaker panel, moderated by Rob Henson, manager, business development at Uniti Titanium, Moon Township, PA, which sponsored the session; and Titanium Mill Processing and Melting, moderated by Donald E. Larsen, Jr., plant manager, ti-ingot, Alcoa Howmet, also focused on next-generation manufacturing capabilities. Industrial/Automotive The Industrial/Automotive speaker panel also provided examples of advanced manufacturing. “Optimization Of The Chemical Milling Of Investment-Cast Titanium Alloys,” a paper by Silvia Gaiani, materials and technologies consultant, Akrapovic d.d., a car exhaust system suppler from Slovenia, described her company’s work regarding chemical milling on two common titanium alloys: Ti-6Al-4V (titanium/aluminum/vanadium) and Commercially Pure Grade 2 titanium. Compared with other forming methods for titanium, Gaiani said investment casting offers greater flexibility to produce complex components in near-net shape. However, the process has its share of challenges due to titanium’s high reactivity in the molten state, which makes it susceptible to contamination by interstitial elements (carbon, nitrogen, oxygen) dissolved from the mold. The contamination manifests itself in a brittle “alpha-case” layer that negatively affects the mechanical properties of the titanium casting. Akrapovic has done research to evaluate metal-removal rates of various chemical baths for industrial-scale use to remedy this problem. Gaiani outlined chemical milling and pickling baths used by Akrapovic to remove and/or minimize the formation of the alpha-case layer. Tested solutions demonstrated a tendency to “remove a bigger quantity of material where the wall thickness is higher,” she said. “In the case of cast components with narrow tolerances, this aspect should be carefully taken into account in order to fulfill the project requirements of the finished product.” In addition, she said that in order to assure the correct service conditions of the bath on an industrial scale, it’s important to maintain the amount of titanium dissolved into the solution.” Fu Baoquan, a professor of engineering at Western Superconducting Technologies (WST) Co. Ltd., Xi’an, China, presented “Research and Production of Titanium Alloy for Aviation Industry.” Baoquan’s talk reviewed the development of WST’s titanium alloys that target aerospace applications, such as a Ti-6Al-4V alloy for fan disks and structure parts. Other WST alloys, such as titanium/niobium (Ti-Nb) and titanium/aluminum/tin (Ti-Al-Sn), which target a wide assortment of industrial applications in China, have been developed to optimize fracture toughness, anti-corrosion, welding and machining properties. Energizing the Global Supply Chain Thomas Zuccarini, manager, medical and consumer markets and sales administration for Dynamet Inc., a unit of Carpenter Technology Corp., Wyomissing PA, led a panel discussion on “Creating Supply-Chain Value for the Medical and Dental Device Industries into the Future.” Donald Urbanowicz, the principal of Urbanowicz Consulting LLC, offered suggestions on “Sustaining Innovation within the Orthopedic Industry.” Urbanowicz opened his presentation by acknowledging the value proposition for a supply chain, especially as it relates to cultivating innovation, currently is under intense scrutiny. Innovative executives along the supply chain must remain focused on the core mission, but also need to be open to the opportunities for diversification. In order to drive innovation, Urbanowicz suggested three steps: solicit input from supply-chain associates on a regular basis in order to allow ideas to “percolate up”; manage business time for make room for “unofficial activity” and step back and ponder creative ideas; and establish a realistic, pragmatic process for “turning ideas into reality.” In his summary, he said the “status quo is not an effective go-forward strategy to drive innovation.” Novel, low-risk ideas need to be quickly benchmarked and tested, and business leaders should remain open minded to identify opportunities for innovation. Based in Chatham, NJ, Urbanowicz Consulting is a medical advisory firm with a musculoskeletal focus. According to information on the company Web site, Urbanowicz, for 30 years, has served in various leadership roles with multinational healthcare companies, with executive responsibilities in management, global marketing and sales, strategic planning and business development. Master Dissertations on Titanium Mike Royer, Director of Manufacturing of AMETEK - Reading Alloys, served as the moderator for the “Best Master Dissertation on Titanium” panel, which featured three presentations on titanium research. Dr. Neidenei Gomes Ferreira, advisor to Fernanda Lazoni Migliorini, Instituto Nacional de Pesquisas Espaciais (INPE), Brazil, discussed “Production and Characterization of Boron-Doped, Diamong Electrodes Grown on Titanium, Applied to Textile Dye Degradation.” Ferreira is a senior scientist at the INPE. Vi Khanh Truong presented an “Investigation of Bacterial Attachment Patters on Micro- and Nano-Restricted Surface Topographies.” Truong is a research post-doctoral fellow with the Faculty of Life and Social Sciences at Swinburne University of Technology, Melbourne, Australia. Daniel A. Jewell, Ph.D., reviewed “Titanium Metal Production Via Ozycardie Electrorefining.” Jewell is a post-doctoral research associate in the Department of Materials Science and Metallurgy at the University of Cambridge, UK. A select panel of judges at TITANIUM 2012 selected Jewell for delivering the best dissertation.
Additive Manufacturing at TITANIUM 2012
Additive manufacturing, also known as direct digital manufacturing, is the focus of many of the efforts to reduce costs in the production of titanium parts. Additive manufacturing is a family of processes in which parts are first modeled in a CAD program that “slices” them into thin layers. Parts are then built up layer by layer in specialized machines according to the pattern in the program. The machines build up the layers by laser-sintering powder; or by injecting powder at high speed onto a substrate; or by injecting powder into a high temperature plasma, laser beam, or electron beam, where it is melted before striking the substrate. The major benefits of additive manufacturing are reduced waste, speed of production, elimination of the need for tooling, and the production of near-net-shape parts. Because parts are built layer by layer, it is possible to design internal features and passages that could not otherwise be produced. Complex geometries and assemblies with multiple components can be fabricated as a single part, improving reliability and reducing labor cost. Therefore, titanium manufacturers and fabricators are developing these technologies to reduce cost and material waste while still providing the unique benefits of titanium. Technologies such as electron beam-direct digital manufacturing, direct metal laser sintering, laser-engineered net shapes, and ion fusion formation were discussed in several presentations. Northrop Grumman, Honeywell Aerospace, Oak Ridge National Laboratory, U.S. Army ARDEC, and W.A. Gooch Consulting reported on several programs at the conference. The Northrop Grumman presentation reported that advances in electron beam direct digital manufacturing (EB-DDM) have the potential for improved properties and reduced costs for aerospace components. During this process, the electron beam melts metal powder in a layer-by-layer process to build the part. A major benefit is that near-net-shape designs are no longer limited by conventional manufacturing capabilities, and the technology enables fabricating geometries that are challenging or too expensive to manufacture by conventional means. Furthermore, because of the material efficiency of the process, the buy-to-fly ratio is significantly reduced. Faster deposition rates and dimensional control are key to cost savings, and the ability to reduce cost is very dependent on geometry. However, certain challenges remain to be addressed. For example, the current surface finish of electron-beam DDM metal components results in an excessively rough surface for fatigue-rated components. The uneven finish prohibits use of baseline nondestructive inspection techniques such as dye penetrant, eddy current, and ultrasonics. Another issue is the high cost of powder raw material stock, which raises costs. Finally, the application of the technology is limited because of the lack of specific design capabilities and tools within the majority of the engineering community. At Oak Ridge National Laboratory, researchers are working with additive manufacturing providers to develop high-performance materials, low-cost feedstocks, efficient processing techniques, and in-situ characterization and controls. For example, Oak Ridge is collaborating with Arcam on electron beam melting (EBM) technology, to increase the material deposition rate and the build volume. Lockheed Martin is collaborating with Oak Ridge to build titanium brackets for an aerospace application via the EBM process. The technology has the potential to reduce cost of the part by over 50%, and to reduce the buy-to-fly ratio from the current 33:1 down to 1.5:1. Honeywell Aerospace reported on additive manufacturing of titanium alloys by direct metal laser sintering, electron beam melting, and ion fusion formation. During direct metal laser sintering (DMLS), the powder is fused into a solid part by melting it in specific patterns with a focused laser beam having power of 200 to 400 watts. Parts are built up in layers only about 20 microns thick. Highly complex geometries can be built directly from CAD data, without the need for tooling. Parts are net-shape, with high accuracy, good surface quality, and excellent mechanical properties. Build speed is slower than electron beam, but the surface finish is better. Typical dimensional accuracy for Ti-6Al-4V components is +/- 0.005 inch. Ion fusion formation (IFF) is based on a plasma welding torch that melts wire or powder feedstock. The hot plasma (usually consisting of argon ions) is directed to a predetermined spot on the workpiece, and the feedstock is introduced into the plasma stream to produce a pool of molten material at that location. Parts can be built in almost any three-dimensional shape, with high precision and predictable properties. IFF could be a game-changing technology, potentially suitable for difficult- to-manufacture components, and offers the possibility of producing functionally graded materials. Products can be used as-deposited, or post-deposition processed, and/or machined. IFF equipment is not complicated to operate, has low initial capital costs, requires little maintenance, and has low operating costs. It is less expensive than electron beam and laser melting technologies, because the feedstock is melted by electrical energy rather than expensive lasers or electron beams. Challenge areas are that wire feedstock products require post machining, and low-power control/fine feature equipment is currently not installed. Multi-axis build and thermal management capability complicate programming, but also provide more flexibility. The largest barrier to entry into the aerospace marketplace is machine size, because the build envelope of 4 x 4 x 6 feet is too small for many aerospace structures. Although aerospace is the largest market for titanium, the armed services recognize that it is a key material to meet military needs for higher strength, lower weight vehicles and components, better ballistic performance, and improved corrosion resistance. Because of this, the U.S. Army Armament Research and Development Center (ARDEC) works to improve processes such as near net shape technologies, forging, casting, low-cost powders, and advanced machining. ARDEC’s presentation covered the ManTech titanium programs that focus on reducing costs, improving manufacturability, developing new processes, and testing new titanium alloys. Specifically, additive manufacturing processes at ARDEC include electron beam melting, laser cladding, and laser-engineered net shaping (LENS). LENS is a process in which metal powder is injected into the focused beam of a high-power laser under tightly controlled atmospheric conditions. The focused laser beam melts the surface of the base material in a small area, and the powder is absorbed into the molten pool. The resulting deposits range from 0.005 to 0.040 inches thick, and may then be used to build, repair, or clad metal parts for a variety of different applications. The key benefits of this process over traditional techniques are a metallurgical bond; relatively low heat input; minimal stress and distortion created by deposits; and rapid cooling rates. The process is suitable for repairing shafts, cladding aerospace components, and manufacturing free-form parts. In addition to titanium, suitable alloys include nickel, cobalt, Inconel, stainless steel, and hardfacing alloys. Another major military application for titanium is armor. The W.A. Gooch Consulting presentation first described several titanium armor alloys, listing their chemical compositions and mechanical properties, then discussed several advanced processing methods. For example, BAE Advanced Materials (now CoorsTek Vista), has developed a process to hot press large near-net-shape functionally gradient titanium-base tiles in a single stage. On a titanium metal substrate, titanium and titanium/titanium diboride (TiB2) powder mixtures form a titanium monoboride (TiB) hard face that grades through intermediate layers. The TiB ceramic is formed through reaction sintering between the TiB2 and titanium powders during the hot-press phase. TiB is densified as a cermet (ceramic in a metal matrix) to aid in fabrication.
Advanced Titanium Powder Technologies
One of the major topics at Titanium 2012 was additive manufacturing technologies for building net-shape parts of titanium powder. As discussed in previous articles, these technologies include direct metal laser sintering, laser engineered net shaping, electron beam melting, and ion fusion formation. However, all depend on the quality of the powder to achieve final properties. The following resentations focused on advanced technologies to produce high quality powder while minimizing cost. In general, they are already commercialized or are in the pilot-scale stage of development. They include variations on the Kroll process, methods of blending elemental powders, processing blocky powders into spherical shapes, and metal injection molding. Presentations summarized here were by ADMA Products; Institute for Metal Physics; Ametek Reading Alloys; CSIRO; and Element 22. M.V. Matviychuk of ADMA Products discussed “Blended Elemental Powder Titanium Alloys Strengthened by Heat Treatment.” He reported on a study showing that high-strength titanium alloys can be successfully sintered by the blended elemental powder metallurgy (BEPM) approach using titanium hydride powder. In addition, their mechanical properties can be improved with post-sintering processes. The study covered the following alloys: Ti-5Al-5V-5Mo-3Cr, Ti-10V-2Fe-3Al, and Ti-1Al-8V-5Fe. Because of limited space, this summary will consider only the results of the study of Ti-1Al-8V-5Fe, a low-cost/high strength alloy developed in the 1950’s that was discontinued because of the segregation of iron that occurs during melting. In an effort to achieve high properties in this alloy, thermomechanical processing was performed on a billet of Ti-1Al-8V-5Fe that had been produced by a novel low-cost BEPM process in which the base material was TiH2 powder. Hot-working followed by sintering not only eliminated porosity, but also developed microstructures that resulted in high strength. Tensile testing was conducted on the as-rolled and heat-treated materials to evaluate their mechanical properties, and results showed that these matched well with the high mechanical properties produced by conventional processes. Dr. Matviychuk concluded that the study showed the BEPM approach is especially important in the case of alloys that are difficult to produce via ingot metallurgy. For these alloys, the controlled formation of fine grains, reduced porosity during alloy sintering, properly selected post-sinter thermomechanical processing, and correct heat treatment, together enable attainment of properties that meet required highstrength specifications. According to Dr. V.A. Duz of ADMA Products, one of the reasons that titanium powder metallurgy is not fully developed is the lack of low-cost, highquality titanium powder. He pointed out in “Transformational Non-Kroll Process: Hydrogenated Titanium Powder Production” that some of the reasons include chemistry issues, meaning the high content of impurities such as chlorine, magnesium, and sodium; and property issues, meaning inferior low-cycle fatigue properties, low fracture toughness, and weldability problems. He explained that after ADMA researchers completed an extensive review of the various routes of titanium powder production, they decided that only melting can remove impurities and make titanium and titanium alloys acceptable for critical applications. His presentation showed that magnesium reduction of titanium chloride followed by hydrogenation may be the most cost-effective approach to producing high quality titanium powder. Therefore, researchers developed a technology based on breaking up the titanium sponge mass upon its saturation with hydrogen into titanium hydride powder. To produce the powder, titanium tetrachloride is reduced with magnesium, and titanium sponge is purified by vacuum distillation and hydrogenation. An important aspect of the process is introduction of additional titanium hydride powder together with titanium tetrachloride. This added powder positively affects the kinetics of the magnesium reduction process by causing emission of additional atomic hydrogen, which helps to reduce oxides in the system, cleans the interparticle interfaces of the product, and enhances the diffusion between components in the powder mixture. The additional hydrogen considerably reduces vacuum distillation time, increases furnace output, reduces electric power consumption, and reduces labor costs. As a result, the cost of ADMA TiH2 powder is 15% lower than the cost of conventional Ti sponge. A pilot scale unit with a capacity of 660 pounds per run for TiH2 powder production is being built and will be installed by the end of 2012. Another approach that takes advantage of low-cost TiH2 powders was presented by Dr. Colin McCracken of Ametek Reading Alloys. He explained in “Plasma Spheroidized Titanium Powders” that these powders are based on TiH2, and are therefore a lower-cost alternative to powders made via PREP and Gas/Plasma atomization. The plasma spheroidizing process is a high-volume batch process in which blocky hydride-dehydride (HDH)-processed powders are made spherical. The particle size distribution (PSD) range of the powder is predetermined at the HDH process stage, thereby improving powder yield and utilization. The HDH process is based on the fact that titanium has a very high affinity for interstitial elements such as oxygen, hydrogen, nitrogen, and carbon. When heated in a hydrogen atmosphere, a stable but brittle titanium hydride (delta phase) is produced through the following reaction: Ti (s) + H2 (g) <──> TiH2 (s) Titanium hydride can be readily crushed, milled, and screened into titanium hydride powder. These blocky, angular powders are ideally suited for press/sinter, CIP/sinter, roll compaction, and plasma spray. However, for more advanced technologies, the powder particles must be spherical. After much research and development, Ametek/Reading Alloys has developed a low-cost method for making high-purity spherical powder from blocky TiH2 powder. The powder is fed into an induction-coupled plasma field, where the particles are melted and then solidified in spherical shapes. The resulting morphology is very similar to the spherical particles produced by the plasma rotating electrode powder (PREP) process, but is lower in cost. It is free from agglomerates and satellites, thus eliminating argon gas entrapment. The plasmaspheroidized powder has significantly higher apparent density and powder flow compared to the feedstock. The PS process can produce the full range of particle size distribution, from coarse to fine, and PS titanium powders are ideally suited for advanced manufacturing technologies such as HIP, additive manufacturing, and metal injection molding. Another program to produce spherical powders for additive manufacturing was discussed by Dr. Christian Doblin of Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO). He reported on “The Ongoing Development of the TiRO Process,” which is based on the chemistry of the Kroll batch process, in which titanium tetrachloride is reduced with magnesium. The goal of the TiRO process is continuous production of high-quality titanium powder via fluidized-bed technology. Although the chemistry is similar to that of the Kroll process, TiRO operates within a temperature range suitable for fluidized bed technology. It exploits the principle that when suspended in a gas, solid particles behave like a fluid and react more rapidly. Therefore, the Kroll chloride separation step has been redesigned and integrated into the overall TiRO process. The result is a powder production system capable of continuously producing high quality titanium powder suitable for near net-shape manufacturing in a fraction of the time with minimal waste. Moreover, process conditions can be adjusted to generate particles tailored in shape and size to suit differing downstream applications. This is an advantage for fabrication methods in which the powders can be consolidated directly, thereby avoiding remelting. The powder product can be designed for downstream techniques such as hot isostatic pressing, metal injection molding, cold spray, and laser forming. Over a two-year timeframe, CSIRO has refined the fluidized-bed reactor and built a pilot-scale system with production capacity of 2.0 kg/hour. This reactor is suitable for scale-up to commercial size, and will support development of a demonstration plant with a capacity of 100 metric tons per year. The project currently stands poised for scale-up to commercial production. Matthias Scharvogel of Element 22 described how spherical powders could be used in metal injection molding (MIM), which features only one working step: the filling of the injection mold. This step determines the final geometry, which can be so complex that it would be either impossible or much too expensive to produce by conventional methods. To begin the process, the metal powder is mixed with a binder, forming a feedstock that is pressed by a conventional commercial injection machine into a mold under high pressure at approximately 100°C. The pressed green part has the final geometry, but it is very frangible. In the next step, the binder is removed in a multi-stage chemical and thermal process, resulting in a metal part with high porosity. In the final step, the part is sintered at approximately 1200°C to consolidate the powder and form a strong solid metal component. Up to now, the strong dependence of titanium mechanical characteristics on the content of oxygen, nitrogen, and carbon in particular, have ruled out any commercial use of this technology. However, in co-operation with research-institutes, Element22 has been able to overcome these problems and is now capable of producing components from Ti-6Al-7Nb with mechanical properties equivalent to those made by conventional techniques. Therefore, titanium parts made via MIM are now being produced for medical devices. Titanium and its alloys are nearly ideal materials for medical technology, especially for implants, because it is neither toxic nor rejected by the human body, nor does it induce allergic reactions. In addition, titanium materials are nonmagnetic and therefore trouble-free for magnetic resonance imaging (MRI). With these properties and the ability to make small complex parts, titanium MIM devices are making inroads into the medical market.
Titanium Advanced Manufacturing at TITANIUM 2012
Titanium is the ninth most abundant metal in the Earth’s crust, but despite its many advantages, its high cost has limited its applications. These presentations from Tricor Metals, Cambridge University, the Boeing Company, and RTI International Metals show that costs can be reduced by finding more cost-effective ways to extract the ore as well as improved manufacturing methods. However, Charles S. Young of Tricor Metals made the case in “Titanium is Not Too Expensive,” that titanium is really less expensive than many other corrosion-resistant alloys. He showed that rather than price per pound, the cost should be based on a more realistic measure that considers the cost of protecting a given surface area, a cost he designates the “normalized cost.” In other words, it is the cost of the amount of material required for a part that is important, not the cost per pound. Because each metal or alloy has a different density, a square foot of a metal with lower density would weigh less at a given thickness than one with higher density. In addition to density, yield strength needs to be considered when attempting to compare the true cost of different alloys. Therefore, the normalized cost takes into account both density and yield strength. Normalized cost can be calculated by this equation: Normalized Cost = Price/lb x Density x (YS of alloy/YS of titanium) This equation shows that the normalized cost of Titanium Grade 2 is significantly lower than that of nickel alloys 625 and C276. This is a very significant difference, and the titanium industry should educate industrial end-users about this difference. This approach can provide a quick comparison of metals and alloys, but ASME Design Allowables (Section VIII Div 1) should also be taken into account. This can easily be done by substituting Design Allowable strengths at operating temperature for the Yield Strength in the Normalized Cost equation. The equation works to compare any metals at any operating temperature. In fact, this same type of analysis is suitable for heat transfer equipment, and it shows that currently titanium is more cost-effective than copper-nickel alloys. A process for titanium extraction that would reduce costs even further was explained by Dr. Daniel Jewell of Cambridge University. He discussed “The Chinuka Process: Titanium Metal Production via Oxycarbide Electrorefining.” This technology replaces the expensive multi-step Kroll process with one in which refining and electro-deposition take place simultaneously, with ores and concentrates as feedstock. It allows impure metal oxides to be reduced and refined to high-purity metals. Initial work has focused on refining natural rutile concentrates through three simple steps: Reacting the concentrate with carbon at 1700°C to form oxycarbides;
Making these oxycarbides the anode in an electrolytic bath at around 800°C; and Ionizing and dissolving metals in the oxycarbide in the electrolytic bath according to their electrode potentials. Once in the electrolytic bath, the metal ions again deposit in accordance with their electrode potentials, with the result that the impurities either remain at the anode, or are retained in the electrolyte, from which some evaporate. In this way, it is possible to reduce and electroextract-refine impure titanium concentrates to pure titanium. Deposits consist of pure titanium metal crystallites, sponge, or powder with a particle size range of 1 to 30 microns. In addition to standard grade concentrate, the process has been successfully applied to fine and ultra-fine concentrates, as well as to combinations of the concentrates plus ilmenite, a less expensive form of titanium dioxide feedstock. Unlike carbo-chlorination and treatment in sulfuric acid, the particle size and calcium oxide content are immaterial. Dr. Jewell noted that the electro-extractive FFC-Cambridge Process, the flagship Kroll replacement technology, is unable to accept any significant cationic impurities in the feedstock, as these would be retained in the final product. However, “although this is a bane for pure metal production, it is a boon for producing alloys, where the FFC-Cambridge process excels.” In 2013, research will continue at Cambridge University, where an experienced team of academics and researchers has been assembled. Whatever the method of production, titanium has become an important component for both military and civilian jet aircraft at the Boeing Company, according to a presentation by Daniel Sanders. In addition to low density and high strength, titanium alloys are very compatible with composite materials, such as graphite-containing plastics, because of their similar galvanic properties and coefficient of thermal expansion. However, the manufacture of titanium aerospace components can be very expensive by traditional methods. Therefore, Boeing engineers are exploring several technologies that offer advantages over existing options. For example, airframe castings have traditionally been net forging geometries, descended from sheet metal geometries. Consequently, one goal is to redefine structure geometries to optimize the 3-D capabilities of titanium castings. Additive manufacturing technologies enable direct fabrication of parts without part-specific dies. In fact, such parts are qualified for flight and are in production. However, the ability to reduce cost is very dependent on geometry. Cost savings depend on faster deposition rates and dimensional control. Nearer-net shape die forgings are also being developed. Forging titanium above the beta transus allows for lower flow stresses and the ability to form a nearer-net-shape part with equivalent press capacity. Larger forging presses and additional blocker dies result in improved definition. In addition, advanced forging modeling allows for optimizing the forging sequence. Another effort is development of superplastic forming of complex contoured structures, with friction stir welding as the joining method. As a solid state weld, friction stir welding involves no melting, and produces a fine grained microstructure. It results in components with a low occurrence of defects such as cracks and porosity, as well as exceptional static and fatigue properties. Superplastic forming was also the focus of the presentation by Ernie Crist of RTI International Metals. He reported on developments in superplastic forming/diffusion bonding of Ti-64 and Ti-6242 alloy sheets. Deep alpha case forms, and this requires removal by expensive and non-environmentally friendly chemical milling. Therefore, reducing SPF temperatures and cycle times would enable more cost-effective fabrication of parts. Toward this end, RTI engineers have devoted significant effort to developing Ti-64 sheet that is superplastic at temperatures in the range 1450-1500°F (788–816°C). In addition, aero-engine components currently manufactured from Ti-64 sheet are being converted to Ti-6242 to meet the demands of elevated temperature requirements. Consequently, OEMs and Tier 1 suppliers have expressed an interest in Ti-6242 sheet that exhibits “low-temperature” SPF behavior at or below 1550°F (843°C). As with Ti-64, lowering the SPF temperature would improve die life and eliminate the need for chemical milling. As steps toward this goal, engineers have utilized pilot-scale facilities to establish critical process parameters; designed computer simulations to validate load and torque requirements for the production rolling mill; and completed characterization of SPF behavior by established ASTM practices, such as ASTM E-2448. Properties of production-size sheets have been validated in SPF presses at RTI Advanced Forming. Today, Ti-6Al-4V production-scale finegrain sheets (FGS) have been fabricated, and successful SPF trials have been carried out at 1425-1475°F (774-800°C). Commercialization of Ti-64 sheet is on-going at multiple customer sites. Pilot-scale work on Ti-6242 FGS shows that it is capable of being superplastically formed at temperatures as low as 1550°F (843°C). Production sheets of Ti-6242 have been manufactured, and customer validation plans have been established.