摘要
304奥氏体不锈钢管使用过程中在焊接接头附近发生开裂现象,通过宏观和微观观察、化学成分分析、能谱分析和金相检验等方法对不锈钢管焊接接头的开裂原因进行了分析。结果表明:不锈钢管焊接接头的开裂形式为晶间腐蚀导致的沿晶开裂,主要原因是一侧不锈钢管的成分不符合标准,碳含量偏高、铬含量偏低,在焊接加热的过程中发生了焊接敏化现象,降低了焊接接头的耐腐蚀性能,导致焊接接头的热影响区产生腐蚀裂纹,此外钢管中输送的自来水中氯离子较多,提供了腐蚀环境,进一步促进了裂纹的扩展。
304 austenitic stainless steel pipe cracked near the welded joint during use. The causes of cracking on 304 austenitic stainless steel pipe welded joint were analyzed by means of macro and micro observation, chemical composition analysis, energy spectrum analysis and metallographic examination. The results show that the cracking form of stainless steel pipe welded joint is intergranular cracking caused by intergranular corrosion. The main reason was that the composition of stainless steel pipe on one side does not meet the standard, the carbon content of stainless steel pipe was high and the chromium content was low. During the welding heating process, the welding sensitization phenomenon occured, which reduced the corrosion resistance of welded joint and led to corrosion cracks in the heat affected zone of welded joint. In addition, there were more chloride ions in tap water transported by steel pipe, which provided a corrosive environment and further promoted the crack propagation.
作者
曹龙韬
龚兰芳
陈智江
CAO Longtao;GONG Lanfang;CHEN Zhijiang(CRRC Zhuzhou Locomotive Co.,LTD.,Zhuzhou 412001,China)
出处
《理化检验(物理分册)》
CAS
2021年第5期76-79,共4页
Physical Testing and Chemical Analysis(Part A:Physical Testing)
关键词
304奥氏体不锈钢
焊接接头
晶间腐蚀
热影响区
开裂
304 austenitic stainless steel
welded joint
intergranular corrosion
heat affected zone
cracking