激光焊焊前预热和焊后热处理对焊缝质量的影响

Effect of preheating and post-welding heat treatment on weld quality

为了研究激光焊接热处理工艺对焊缝组织和性能的影响,制定了焊前预热和焊后热处理的试验方案。采用金相显微镜和扫描电镜对焊缝组织观察分析,并用HV0.1显微硬度计检测焊缝区域硬度。结果表明,经过焊前预热和焊后热处理的金相组织铁素体明显增多,而珠光体较少,硬度较低,其中焊后热处理对组织和性能改善的最为显著。

In order to study the effect of laser welding heat treatment process on the microstructure and properties of weld,pre-welding and post-welding heat treatment were established. Metallographic microscope and scanning electron microscope were used to observe and analyze the microstructure of the weld,and used HV0.1 microhardness tester to measure the hardness of the weld area. The results showed that by means of pre-welding and post-welding heat treatment, the ferrite in the metallographic structure increased obviously,while the pearlite was less and the hardness was lower,especially the post-welding heat treatment improved the microstructure and properties most significantly.