摘要
用恒变形U型弯曲试样应力腐蚀试验研究了Sn粘附的304不锈钢在155℃、45 wt% MgCl_2溶液中的应力腐蚀行为。采用扫描电镜观察了样品腐蚀前后的显微形貌,采用能谱分析仪检测了样品的元素组成。结果表明,不锈钢在MgCl_2溶液中浸泡后为局部腐蚀,主要表现晶内腐蚀特征;表面局部被Fe-Sn化合物粘附的不锈钢,金属间化合物转变为腐蚀产物,裂纹沿应力方向生长;Sn的电极电位较低,金属间化合物优先被腐蚀,腐蚀坑内的酸性增加,Sn粘附降低了不锈钢的耐腐蚀性。
The stress corrosion cracking （SCC） behaviors of 304 stainless steel adhered by Sn were studied using constant strain U-bending samples in 45 % MgCl2 solution at 155 ℃. The morphology of the samples before and after corrosion tests were observed by SEM. The element composition of the samples was detected by EDS. The results show that local corrosion appears on the surface of stainless steel eroded in MgC12 solution. It expresses transgranular corrosion characteristics. The interrnetallics compound transforms into corrosion products for the sample adhered by Fe-Sn. The cracks grow along the stress direction. The intermetallics compound are preferentially eroded because of lower electrode potential of Sn, which can lead to acidity increasing in corrosion hole. The corrosion resistance of the stainless steel reduces because of Sn adherence.
出处
《热加工工艺》
CSCD
北大核心
2015年第24期107-109,共3页
Hot Working Technology
基金
国家自然科学基金资助项目(51175240)
关键词
低熔点金属Sn
不锈钢
应力腐蚀
low melting point metal Sn
stainless steel
stress corrosion
