Titanium alloy has high strength, low density, good mechanical properties, good toughness and corrosion resistance. In addition, titanium alloy has poor processing performance and is difficult to cut. In hot working, it is very easy to absorb impurities such as hydrogen, oxygen, nitrogen and carbon. There is also poor abrasion resistance and complex production process. The industrial production of titanium began in 1948. The demand for the development of the aviation industry makes the titanium industry develop at an average annual growth rate of about 8%. At present, the annual output of titanium alloy processing materials in the world has reached more than 40000 tons, and there are nearly 30 kinds of titanium alloy brands. The most widely used titanium alloys are Ti-6Al-4V (TC4), Ti-5Al-2.5Sn (TA7) and commercially pure titanium (TA1, TA2 and TA3).
Titanium alloy is mainly used to make compressor components of aircraft engines, followed by structural components of rockets, missiles and high-speed aircraft. In the mid-1960s, titanium and its alloys were used in general industry, such as making electrodes for electrolysis industry, condensers for power stations, heaters for petroleum refining and seawater desalination, and environmental pollution control devices. Titanium and its alloys have become a corrosion resistant structural material. In addition, it is also used to produce hydrogen storage materials and shape memory alloys.