Can the strength of Grade 2 titanium be improved by cold working

Yes, the strength of Grade 2 commercially pure titanium can be significantly improved by cold working.

Grade 2 is a non-heat-treatable material, meaning it cannot be strengthened by conventional heat treatment processes such as solution treatment, quenching, or aging. However, it responds very well to cold working - including cold rolling, cold drawing, stamping, bending, and swaging. During cold deformation, a large number of dislocations form and multiply inside the metal microstructure, which hinders further plastic deformation and directly increases yield strength, tensile strength, and hardness.

As the℃of cold deformation increases, strength and hardness keep rising, while ductility and formability decrease accordingly. By controlling the amount of cold work, manufacturers can produce Grade 2 products in different tempers to meet various application requirements. Therefore, cold working is the most effective and commonly used method to enhance the mechanical strength of Grade 2 titanium.

For long-term reliable service, the recommended upper continuous operating temperature for Grade 2 titanium is approximately 315℃ (599℃F).

In short-term or non-critical applications, it can temporarily withstand temperatures up to about 425℃ (797℃F). Beyond this range, several issues occur:

For applications involving long-term high temperature, creep, or structural loading, 315℃ is widely accepted as the safe upper limit in engineering standards. If higher temperature performance is required, alloyed titanium grades or other high-temperature materials should be used instead.