模具修复的搅拌摩擦点焊工艺研究

Research on Process of Friction Stir Spot Welding for Repair Die

选择搅拌摩擦点焊技术,进行了Cr12MoV失效模具的修复工艺研究,并进行了显微组织、表面硬度、耐磨损性能和热疲劳性能的测试分析。结果表明,搅拌摩擦点焊可成功实现Cr12MoV失效模具的高质量修复;与失效模具相比,搅拌摩擦点焊修复后模具的表面硬度可提高18 HRC、磨损体积减小82.4%、0℃冲击韧度是修复前的13倍;优选的搅拌摩擦点焊工艺参数为:搅拌头旋转速度1250 r/min、焊接时间5 s、轴肩下压量0.3 mm。

The Cr12MoV failure die was repaired by friction stir spot welding with different process parameters, and the microstructure, surface hardness, wear resistance and thermal fatigue property were tested. The results show that the Cr12MoV failure die is successfully repaired with high quality by friction stir spot welding. Compared with the failure die, the friction stir spot welding could make surface hardness of the repaired die increase by 18 HRC, make wear volume decrease by 82.4%, and the impact toughness is 12 times as much as the die before repairing. Moreover, the optimized process parameters are the rotation speed of 1250 r/min, welding time of 5 s and shoulder plunge depth of 0.3 mm.