Titanium and titanium alloy has a perfect strength and weight ratio, good toughness and corrosion resistance. Titanium alloy is mainly used for manufacturing aircraft engine compressor parts and structural parts of missile and high-speed aircraft. In the mid-1960s, titanium and its alloys were used in the general industry to make electrodes for the electrolytic industry, condensers for power stations, heaters for oil refining and desalination and environmental pollution control devices, as well as hydrogen storage materials and shape memory alloys.
At present, the annual production capacity of titanium alloy in the world has reached more than 40,000 tons, with nearly 30 kinds of titanium alloy grades. In heat processing, impurities such as hydrogen, oxygen, nitrogen and carbon are easily absorbed. Due to the poor processability, it is difficult and complex to cut and reprocess for Ti and its alloy. Annealing is implemented to eliminate internal stress, improve plasticity and produce an optimum combination of ductility, machinability, and dimensional and structural stability. The commonly used heat treatment methods of titanium alloy including full annealing, solution and aging treatment. In addition, double annealing, isothermal annealing, dehydrogenation treatment, deformation heat treatment and other metal heat treatment processes are adopted.