Advances in Technologies and Market Opportunities
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.”