摘要
采用沸腾硝酸法分别对经过敏化处理与未经过敏化处理的316L不锈钢试样进行了晶间腐蚀实验,通过对腐蚀速率和金相结构的比较,可以得出:两组试样的腐蚀速率均为递增的趋势,且第三周期的腐蚀速率明显高于前两周期;敏化处理会减弱316L不锈钢耐晶间腐蚀的能力,且随着时间的延长减弱的幅度在增加;敏化处理导致316L不锈钢耐晶间腐蚀能力下降的原因是由于材料中出现了贫铬区,且铬的析出量是随着晶粒尺寸的增大而降低的,因此在小晶粒集中区域铬的析出量更大,腐蚀更严重。
Making use of boiling nitric acid solution, the intergranular corrosion experiment on the unsensi- tized 316L stainless steel samples was conducted. Comparing corrosion rate and metallographic structure shows that, the corrosion rate of two groups of samples becomes increasing and that of the third cycle gets apparently higher than that of the first two cycles. Sensitizing treatment would weaken 316L stainless steel＇ s resistance a- gainst the intergranular corrosion and the weakened range would be increased with time. The reason weakening 316L stainless steel＇ s resistance against the intergranular corrosion can be chromium-depleted region appeared in materials and precipitation quantity of the chromium decreases with the increase of grain sizes, thus the pre- cipitation quantity of chromium in small grain area becomes greater and the corrosion there becomes more seri- ous.
出处
《化工机械》
CAS
2015年第6期754-758,共5页
Chemical Engineering & Machinery
基金
国家科技重大专项课题资助项目(2011ZX06004-009)
关键词
316L
敏化处理
晶间腐蚀
金相分析
316L, sensitizing treatment, intergranular corrosion, metallographic analysis
