Q345R钢埋弧焊焊缝开裂原因分析  

Analysis of Weld Cracking of Q345R Steel Submerged Arc Welding

作　　者：黄静 赵国仙[1] 宋洋 HUANG Jing;ZHAO Guoxian;SONG Yang(College of Material Science and Engineering,Xi’an Shiyou University,Xi’an 710065,China;Xi’an Maurer Petroleum Engineering Laboratory Co.,Ltd.,Xi’an 710065,China)

机构地区：[1]西安石油大学材料科学与工程学院,西安710065 [2]西安摩尔石油工程实验室股份有限公司,西安710065

出　　处：《焊管》2020年第3期56-62,共7页Welded Pipe and Tube

基　　金：国家自然科学基金“高强低合金钢在高含H2S环境中的SSC机制研究”(项目编号51271146)。

摘　　要：采用宏观分析、化学成分分析、力学性能测试、金相检验及扫描电镜断口分析等手段,对埋弧焊Q345R钢过程中焊缝发生开裂的原因进行了分析。结果表明:裂纹附近金属中的夹杂物、显微组织等检测结果未见异常,但裂纹表面的S元素含量偏高,这是因为在焊剂中存在S元素,经焊接冶金反应生成了硫化物,根据裂纹的特点判断焊缝产生的裂纹属于热裂纹中的结晶裂纹。By means of the macroscopic analysis,the chemical composition analysis,the mechanical property test,the metallographic examination and the SEM fracture analysis,the causes of the welding seam cracking during the submerged arc welding Q345R were analyzed.The results showed that there were no abnormal inclusions and the microstructure in the metal near the crack.However,the content of S element on the crack surface is high,because of the presence of the sulfur in the flux,which is generated by the welding metallurgy reaction.According to the characteristics of the crack,it is concluded that the weld crack belongs to the crystal crack in the thermal crack.

关 键 词：埋弧焊 Q345R 焊缝 热裂纹 结晶裂纹 

分 类 号：TG172.5[金属学及工艺—金属表面处理]