【摘要】 本文建立了以热电偶为温度传感器的激光焊接热循环检测系统，利用２ｍｍ低碳钢板和１．６ｍｍ超细晶粒钢研究了 ＣＯ_２激光深熔焊的热循环特点。结果发现，激光焊的最大加热速度可达 ９００００℃／Ｓ．最小ｔ_８／５为 ０．１３ｓ。同时研究了激光焊接超细晶粒钢时热循环对热影响区尺寸和接头组织性能的影响。更多还原

【Abstract】 A set of computerized system with thermal couples to measure the thermal cycle during penetration laser beam welding has been developed. The thermal -cycle cruve and the heating-and-cooling cruve can be obtained in time during laser welding. By using the system, the characteristics of thermal cycle in CO₂ laser welding were investigated with 2mm mild steel plate and 1. 6mm super -fine-grain steel plate. It shows that the maximum of heating rate is about 90000 ℃/s,and the minimum of t_8/5 is about 0.13s in laser beam welding. The effect of the thermal cycle on the HAZ size and the mechanical properties of the joint of super-fine-grain steel has also been studied.更多还原