SA508-3钢回火焊道技术焊道搭接量的分析

针对核电设备常用钢种SA508-3钢，采用钨极氩弧自动焊接方法，对该钢种在使用回火焊道焊接技术修复时的焊道搭接量进行了分析。试验结果表明，焊道搭接量在0%～30%时，相邻的焊道间有明显的凹坑的存在，在后续焊道的焊接过程中容易出现未熔合问题；焊道搭接量达到70%时，焊道表面向瘤状发展，不利于后续焊道的排布，焊道几何尺寸的排布使得回火焊道焊接技术无法实施；焊道搭接量在40%～60%时，焊道分布相对平直，显微硬度及淬硬组织分布均匀，利于回火焊道技术的实施。

Analysis of amount of lap in temper bead welding of SA508-3 steel

Temper bead TIG welding of SA508-3 steel with weld overlap was studied. The result shows that there were obvious scallops between the adjacent welds when the overlap arrange from 0 to 30%, which was easy to form the lack of fusion problem. When the overlap excess 70%, the weld surface turns to tumor which was bad to deposit subsequent welds, which resulted in that the temper bead welding technique cannot be carried out. Welds surface was relatively flat when the overlap arrange from 40% to 60%, the micro hardness and hardening microstructures distribute uniformly.