高氮奥氏体不锈钢的腐蚀行为研究  

Corrosion Behavior of High Nitrogen Austenitic Stainless Steels

作　　者：吴欣强[1] 付尧[1] 柯伟[1] 徐松[2] 冯兵[2] 胡波涛[2] 陆佳政[2] 

机构地区：[1]中国科学院金属研究所中国科学院核用材料与安全评价重点实验室辽宁省核电材料安全与评价技术重点实验室,沈阳110016 [2]湖南省电力公司科学研究院,长沙410007

出　　处：《中国腐蚀与防护学报》2016年第3期197-204,共8页Journal of Chinese Society For Corrosion and Protection

基　　金：国家电网公司总部科技项目(KG12K16004);中国科学院金属研究所创新基金项目资助

摘　　要：研究了无镍高氮高锰奥氏体不锈钢(HNSSs)的均匀腐蚀、晶间腐蚀、缝隙腐蚀、点蚀性能及再钝化性能;与商用316L不锈钢(316LSS)对比,考察了冷变形、敏化处理等对HNSSs的微观组织、钝化膜特征及耐蚀性的影响。结果表明:固溶HNSSs的均匀腐蚀和晶间腐蚀抗力明显不如316LSS的,敏化处理不影响钢的均匀腐蚀抗力,但导致晶间腐蚀抗力急剧弱化,尤其是无Mo钢;固溶HNSSs的缝隙腐蚀和点蚀抗力优于316LSS的,特别是含Mo钢,敏化处理导致钢的缝隙腐蚀和点蚀抗力弱化;冷变形引入大量微观缺陷,导致钝化膜变薄,膜中稳定氧化物减少,保护性变差,降低了HNSSs在含Cl-溶液中的点蚀抗力,但改善了其再钝化性能;敏化析出χ相,导致HNSSs的耐蚀性下降,再钝化性能劣化,且随冷变形量增加更为显著。并讨论了HNSSs的腐蚀机理。The corrosion performance of Ni free and Mn alloyed high nitrogen austenitic stainless steels（HNSSs）, including uniform corrosion, intergranular corrosion, crevice corrosion, pitting corrosion and repassivation,was investigated by means of immersion test and electrochemical test. The effect of cold work and sensitization treatment on the microstructure, characteristic of passive film and corrosion resistance of the HNSSs was examined. It was found that the solution-annealed（SA）HNSSs had much weaker resistance to uniform- and intergranular- corrosion compared to the SA316 LSS. The sensitization- treatment（ST） hardly affected the uniform corrosion resistance of all the steels, but resulted in rapid degradation of the resistance to intergranular- corrosion, especially for the Mo free HNSSs. The SA HNSSs had a better resistance to crevice- and pitting- corrosion than the SA 316 LSS, in particular the Mo bearing HNSSs. The ST degraded the resistance to crevice- and pitting-corrosion of the HNSSs. The cold work degraded the pitting-corrosion resistance of the HNSSs in chloride- containing solutions through thinning the passive film and decreasing thestable oxides in the passive film, but it improved the repassivation ability of the HNSSs. The ST-induced precipitation of χ phase degraded the corrosion resistance and repssivation ability of the HNSSs, and such degradation became aggravated with increasing cold work degree. Furthermore, the relevant corrosion mechanism is also discussed.

关 键 词：高氮不锈钢 冷变形 敏化 钝化膜 再钝化 

分 类 号：TG172.82[金属学及工艺—金属表面处理]