激光淬火后40Cr与Cr12MoV固态焊接的工艺研究

摘要

By use of solid-state welding experiments for 40Cr steel and Cr12MoV after surface laser quenching pretreatment respectively, the influence of welding process parameters such as temperature, welding time, strain rate, heat preservation process on the quality of welding was discussed. When the welding temperature was low, the tensile strength was low. But the welding temperature was too high, the oxidation stability was low, and meanwhile productivity would decline and it went a gainst energy saving. When the welding time was too long the grain grew larger, the joint intensity decreased. Surface microstructure was refined significantly by surface laser quenching, and the superplasticity mechanism displayed fully. The experi mental results showed that when preloading stress was 56.6 MPa, heating temperature was 800 ℃, welding time was 5 min, holding time was 10 rain, high quality solid state welding could be obtained.%利用对40Cr钢与Cr12MoV钢分别进行表面激光淬火预处理后进行固态焊接试验，探讨了焊接工艺参数（焊接温度、焊接时间、应变速率、保温过程等因素）对焊接质量的影响。焊接温度过低，拉伸强度不高，但焊接温度太高材料抗氧化性下降，同时对提高生产率、节能降耗产生不利影响。焊接时间过长，晶粒长大，接头强度降低。表面激光淬火使表层组织显著细化，超塑性机制得到充分发挥。试验结果表明：预压应力为56．6MPa，加热温度为800℃，焊接时间为5min，保温时间为10min可达到高质量的固相焊接。