The low density of titanium alloy can reduce the inertia mass of moving parts, and at the same time, titanium valve spring can increase the free vibration, weaken the vibration of car body, and improve the engine speed and output power.
Reduce the inertia mass of moving parts, thereby reducing friction and improving the fuel efficiency of the engine. Choosing titanium alloy can reduce the load stress of related parts and reduce the size of parts, thus reducing the quality of engine and vehicle. The reduction of inertia mass of parts weakens vibration and noise, and improves engine performance. The application of titanium alloy in other parts can improve the comfort of people and the aesthetics of cars. In the application of automobile industry, titanium alloy has played an inestimable role in energy saving and consumption reduction.
Although titanium alloy parts have such excellent properties, there is still a long way to go for titanium and its alloys to be widely used in automobile industry. The reasons include high price, poor formability and poor weldability.
The main reason that hinders the wide application of titanium alloy in automobile industry is the high cost.
The price of titanium alloy is much higher than other metals, whether it is initial smelting or subsequent processing. The acceptable cost of titanium parts in automobile industry is 8 ~ 13 USD /kg for connecting rod, 0 ~ 20 USD /kg for air valve, and less than 8 USD /kg for spring, engine exhaust system and fastener. It is 6 ~ 15 times that of aluminum plate and 45 ~ 83 times that of steel plate.
Titanium alloy is an alloy composed of titanium and other elements. There are two kinds of isomorphic crystals of titanium: titanium is an allotrope with a melting point of 1668℃, which is called α-titanium below 882℃; It has a body-centered cubic structure above 882℃, which is called β-titanium. Using the different characteristics of the above two structures of titanium, adding appropriate alloying elements, and gradually changing the phase transition temperature and composition content of titanium, titanium alloys with different structures (titanium? Alloy).