Application of Titanium and its Alloys for Automobile Parts

Titanium and its alloys have been applied to motorcycles and automobiles in order to reduce the weight of their component parts. In recent years, titanium exhaust systems, engine valves and connecting rods have been widely applied mainly to sports type or large motorcycles. In addition to Ti-6Al-4V, Ti-Al-Fe alloys which utilize Fe as an inexpensive and a common alloying element are used for engine valves and connecting rods. In exhaust systems, such as mufflers, at first, Gr.2 commercially pure titanium sheets have been mainly used because of their high cold formability. Furthermore, several titanium alloys to which Cu, Al, Si and Nb are added have been actively developed in order to improve strength, creep properties, oxidation resistance and so on at elevated temperatures, as service temperature becomes higher. Also, due to the development of processing technologies, the same methods and processes that are used for manufacturing steel parts have been applied to titanium ones, and the application of titanium has recently been expanded to fracture-split connecting rods and fuel tanks. Newly, titanium foil has been adopted as a separator of PEFC used in fuel cell vehicles from the viewpoints of excellent corrosion resistance and cold formability. As mentioned above, in this presentation, the technical contents of titanium products and parts developed for motorcycles and automobiles are reviewed.