摘要
对比分析了不同Mo含量的316L、904L、S31254和S31254-B奥氏体不锈钢在10%NaCl溶液中的腐蚀行为,及其固溶处理、低温时效处理对其耐蚀性的影响;利用扫描电子显微镜、电化学极化曲线和电化学阻抗谱对4种不锈钢的显微组织、耐蚀性和表面腐蚀形貌进行了分析。结果表明:4种不锈钢在10%NaCl溶液中有不同的耐蚀性能,耐蚀性排序为:低温时效态>固溶态,S31254-B>S31254>904L>316L。Mo含量的提高、微量合金元素B加入奥氏体、低温时效处理均有利于提升材料的耐蚀性能。B促使表面形成富Cr、Mo氧化物的钝化膜,提升钝化层的致密化,减缓晶界处贫Cr、贫Mo区,提高耐蚀性。
The increase of Mo content can improve the corrosion resistance of austenitic stainless steel.In this paper,the corrosion behavior of four austenitic stainless steels 316L,904L,S31254 and S31254-B with different Mo content in 10%NaCl solution has been comparatively examined.The effect of solution treatment and low temperature aging treatment on the corrosion resistance of steels was compared.The microstructure,corrosion resistance and surface corrosion morphology of the four stainless steels were characterized by means of scanning electron microscope,electrochemical scanning polarization curves and electrochemical impedance spectroscope.The results show that the four stainless steels present different corrosion performance in 10%NaCl solution,their corrosion resistance can be ranked as follows:low temperature aging state>solid solution state for all steels;whilst S31254-B>S31254>904L>316L.The increase of Mo content,the addition of B and the aging treatment at low temperature can improve the corrosion resistance of the steels.Meanwhile,B can promote the formation of Cr-and Mo-rich oxides in the outer layer of passivation film,which makes the surface of passivation film much compact,and the lean-Cr and-Mo regions at grain boundaries can be slowed down,therewith the corrosion resistance of the steels can be improved significantly.
作者
吕迎玺
LV Yingxi(Shanxi Mechanical and Electrical Design and Research Institute Co.Ltd.,Taiyuan 030009,China)
出处
《中国腐蚀与防护学报》
CAS
CSCD
北大核心
2022年第5期765-770,共6页
Journal of Chinese Society For Corrosion and Protection
关键词
奥氏体不锈钢
耐蚀性
电化学腐蚀
MO
Austenitic stainless steel
corrosion resistance
electrochemical corrosion
Mo
