Application of titanium alloy in automobile components
I. Titanium and titanium alloy have developed into a new type of metal structural material after the second world war due to the aviation and space industry. But because of its difficult smelting technology more, the high production cost and the expensive price make the titanium alloy is only applied in the aerospace industry. With the continuous improvement of the titanium metallurgy production technology and reduction of production cost, titanium has been gradually widely applied in the fields outside aerospace industry, such as biomedical equipment, petrochemical industry, marine engineering, energy industry, sports equipment and automotive industry .
For cars, the engine uses titanium alloy components to save fuel, reduce vehicle weight, decrease engine noise and vibration and extend the life of mechanical parts. Therefore, the car engine titanium alloy parts can improve engine performance. At present, the application of titanium alloy in automobile engine parts includes connecting rod, valve, valve spring, valve spring seat, turbocharger and exhaust pipe; in automotive chassis parts includes suspension system suspension ring springs, drive shaft, bolts and etc.
II. The basic properties of titanium and the amount stored in the crust of main alloy classification Ti make Ti being the fourth metal element, only second to the stock of Al, Fe, Mg, with melting point of 1668℃, the boiling point of 3260℃. The basic properties are as follows:
1. The small density is higher than the strength; titanium density is 4.51g/cm3, only about half of the steel or nickel alloy, which is higher than the strength of aluminum alloy and high strength alloy steel.
2. Small thermal conductivity: the thermal conductivity of titanium is small, one-fifth of low-carbon steel, one of twenty-fifth of copper.
3. Non-magnetic and non-toxic: titanium is a non-magnetic metal,which will not be magnetized in a large magnetic field, and is a kind of non-toxic metal, which has good compatibility with human tissue and blood, widely used by the medical community.
4. Strong anti-damping performance: going through mechanical vibration and electrical vibration, compared with steel and copper metal, titanium own vibration decay time is the longest.
5. Good heat resistance: due to high melting point, the titanium is classified as the high temperature resistant metal.
6. Low temperature resistance: the toughness and ductility of titanium can be maintained at low temperature, which is an ideal material for low-temperature containers.
7. High inhalation performance: titanium is chemically active and readily reacts with carbon, hydrogen, nitrogen and oxygen at high temperatures.
8. Good corrosion resistance: in the air or oxygen-containing medium, the titanium surface will generate a dense oxide film of strong adhesion and large unreactiveness to protect that the titanium matrix is not corroded.