Titanium and titanium alloys with low density, excellent mechanical properties, good biocompatibility, corrosion resistance, high temperature resistance, low temperature toughness and other characteristics, has been widely used in the field of automotive manufacturing. Titanium alloy density is only 60% of steel, and the strength can reach more than 800MPa, at 500℃ or so still maintain good mechanical properties, and welding and forming performance are good, more than 20 years ago has been applied to the manufacturing of racing cars, greatly reducing the quality of racing engines, and improve the engine performance.
At present, the titanium alloy parts used in automobile manufacturing are mainly distributed in automobile exhaust system, engine system, transmission and vibration damping system and car body frame.
1. Exhaust system
Automotive exhaust system materials are required to have good high temperature mechanical properties and corrosion resistance of S and Cl elements. Traditional exhaust valve assemblies are made of stainless steel, but titanium alloys have been found to be more suitable for use as exhaust valve materials in terms of performance.
2. Engine system
Automotive engine system is the most used parts of titanium alloy in the automotive field. The application of titanium alloy in engine system mainly includes valves, connecting rods, crankshafts, valve seats and other parts. Ti-6Al-2Sn-4Zr-2Mo alloy is used to manufacture exhaust valves. Ti-6Al-4V/Ti B alloy is used to prepare the intake valve, and Ti-Al-Zr-Sn-Mo-Nb-Si/Ti B alloy is used to prepare the exhaust valve. These titanium alloys have good high temperature mechanical properties, oxidation resistance and creep resistance, which can effectively improve the engine performance and increase the automobile speed.
Titanium alloy valve seat has been widely used in racing cars and sports cars, the annual production of more than 250,000 sets, mainly using Ti-6Al-4V or Ti-5Al-2Cr-1Fe alloy preparation, because the shape of the valve seat is relatively simple, so in the mechanical processing requirements are not high, and do not need special surface treatment, the cost is cheaper, In the automotive weight reduction effect is obvious.
Suspension spring is the core component of automobile suspension system. Compared with the steel used for automobile spring, titanium alloy has higher specific strength, lower shear modulus and higher fatigue strength, so it is more suitable for the manufacture of automobile shock absorber spring. Because the deflection of the spring is proportional to the number of turns, and the shear modulus of the material is inversely proportional, therefore, the titanium alloy spring in the same spring reaction, than the steel spring needs less turns, effectively reduce the quality of the spring, save space.
