At present, the basic heat treatment processes of titanium and titanium alloys are stress relief annealing, complete annealing, solid solution and aging treatment. Other processes, such as isothermal treatment, multi-stage annealing and multi-stage aging, are rarely used in production.

1. Solid solution and aging treatment process

Solid solution and aging treatment are actually divided into two steps: solid solution treatment and aging treatment. Solution treatment is the operation of heating, holding and rapidly cooling titanium rods and alloys to room temperature. Aging treatment is the operation of air-cooling after solid solution treatment and holding the workpiece for a certain time. The purpose of solution and aging treatment is that some a-Ti alloys, beta-Ti alloys and a+beta-Ti alloys can not be strengthened by heat treatment, but can only be strengthened by annealing to further strengthen their mechanical properties.

2. Stress relief annealing process

Stress relief annealing is also called incomplete annealing. Its function is to eliminate or reduce the internal stress produced during cold working and to prevent chemical erosion and deformation of workpiece in special environment.

3. Complete annealing process

The purpose of complete annealing of titanium and titanium alloys is to obtain stable metallographic structure and improve physical properties, which is conducive to reprocessing and improving the stability of workpiece size and properties.