一、前言在工业上具有广泛用途的中低强度结构钢的环境断裂问题已愈来愈引起人们的注意,关于氢促使材料脆断倾向增大的研究结果时有报导。16Mng钢作为结构材料要求具有良好的焊接性能,由于焊接接头中存在着咬边、气孔、夹渣等多种宏观和微观缺陷以及残余应力,氢容易在焊缝及热影响区聚集,即使采用低氢焊条等工艺措施防止产生延迟裂纹,在使用过程中与氢环境接 I. INTRODUCTION The environmental fracture problem of medium and low-strength structural steel, which has a wide range of uses in industry, has drawn more and more attention. The research results on the tendency of hydrogen to promote brittle fracture have been reported. 16Mng steel as a structural material requires good welding performance, due to the existence of undercut, porosity, slag and other macro and micro defects and residual stress in the welded joints, hydrogen easily in the weld and heat affected zone aggregation, even with low Hydrogen welding rod and other process measures to prevent the occurrence of delayed cracks, in the process of using hydrogen environment and then