The diffusion zone width of main alloying elements increases and hardness of the frictionweld zone near TC4 titanium alloy side improves after post-weld heat treatment.
经焊后回火热处理后，主要合金元素沿焊合区的扩散区宽度增大；焊合区钛合金侧硬度值显著提高。
2
The fine grain and narrow HAZ were found in friction stir weld and the dynamic recrystallization produces fine grain.