激光热处理对420不锈钢焊缝硬度及抗拉强度的影响  

Effects of Laser Heat Treatment on the Hardness and Tensile Strength of 420 Stainless Steels Welds

作　　者：付龙虎 FU Long-hu(Sichuan Vocational College of Chemical Technology,Sichuan Luzhou 646000,China)

机构地区：[1]四川化工职业技术学院,四川泸州646000

出　　处：《精密成形工程》2022年第5期115-120,共6页Journal of Netshape Forming Engineering

基　　金：四川省高等教育研究中心(GZY21B20)。

摘　　要：目的对420不锈钢焊缝进行激光热处理,研究微观结构对焊缝硬度的影响规律。方法通过光纤激光对420不锈钢进行焊接,然后采用激光对焊缝进行热处理,采用金相显微镜对焊缝微观组织进行分析,并采用显微硬度仪测试焊缝的硬度,采用拉力机对焊缝接头进行抗拉强度测试。结果随着激光加热功率的提高,焊缝抗拉强度没有明显变化;随着激光加热速度的降低,焊缝抗拉强度逐渐增加。当激光加热功率为500 W、加热速度为5 mm/s时,焊缝抗拉强度达到667 MPa。结论采用激光对焊缝进行热处理后,焊缝微观组织中晶粒尺寸变大,焊缝硬度降低,有利于焊缝抗拉强度的增加。The effect of microstructure on the hardness of 420 stainless steel welds was studied by laser heating.The 420 stainless steel was welded by fiber laser,and then the welds was heating treatment by laser,the microstructure of the weld was analyzed by metallographic microscope,the hardness of the weld was tested by microhardness tester,and the tensile strength of the weld joint was tested by tensile machine.With the increase of laser heating treatment power,the tensile strength of the weld had no obvious change.With the decrease of laser heating speed,the tensile strength of the weld gradually increased.When the laser heating power was 500 W and the heating speed was 5 mm/s,the tensile strength of the weld reached to 667 MPa.After heating treatment on the welds by laser,the grain size in the microstructure of the welds becomed larger,the hardness of the welds decreased,and the tensile strength of the welds increased.

关 键 词：420不锈钢 激光热处理 抗拉强度 显微硬度 

分 类 号：TG456.7[金属学及工艺—焊接]