摘要
采用高能喷丸技术在SS400钢焊接接头表面层上制备纳米结构,利用透射电子显微镜分析研究了表面纳米晶层的结构特征,并利用XRD对高能喷丸表面纳米化处理后表面层残余应力进行了分析.同时,应用慢应变速率拉伸试验研究了SS400钢焊接接头在敏感腐蚀介质硝酸盐溶液(98℃±3℃温度下,57%Ca(NO3)2+3%NH4NO3)中的应力腐蚀(SCC)行为.结果表明,经过高能喷丸处理后,试样表层的晶粒可细化至大约10 nm,且在表面形成残余压应力;高能喷丸表面纳米化可以提高SS400钢焊接接头抗硝酸盐溶液SCC性能.
A nanostructured surface layer was fabricated by means of high energy shot peening(HESP) on SS400 steel welded by metal active gas welding process.The refined microstructure in the top surface layer was characterized with transmission electron microscopy,and the residual stress was examined with XRD at the same time.Experimental results show that after the HESP treatment the coarse grains of the surface layer may be refined down into-10 nm scale,and the compressive residual stress on the surface layer be induced.The results of low strain rate tensile experiment of SS400 steel welded joint in solution(Ca(NO3)2 57%+NH4NO3 3%) at 98±3℃ indicate that the resistance of SS400 steel welded joint to stress corrosion cracking(SCC) has been enhanced.The enhancement may be attributed to the combined influences of nanostructured surface layer,compressive residual stress and eliminating micro-defect in welded joint of SS400 steel.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2009年第3期65-68,共4页
Transactions of The China Welding Institution
关键词
SS400钢焊接接头
高能喷丸
表面纳米化
应力腐蚀
SS400 steel welded joint
high energy shot peening
surface nanocrystallization
stress corrosion cracking
