微合金化对高锰奥氏体钢在酸性盐雾环境下的耐蚀性能影响研究  

Effect of Micro-alloying with Cr,N and Al on Corrosion Resistance of High Manganese Austenitic Steel in Acidic Salt Spray Environment

作　　者：常雪婷 宋嘉琪 王冰[2] 王东胜 陈文聪 王海丰[3] CHANG Xueting;SONG Jiaqi;WANG Bing;WANG Dongsheng;CHEN Wencong;WANG Haifeng(School of Ocean Science and Engineering,Shanghai Maritime University,Shanghai 201306,China;Jiangnan Shipbuilding Group Co.,Ltd.,Shanghai 201913,China;State Key Laboratory of Solidification Technology,Northwestern Polytechnical University,Xi'an 710072,China)

机构地区：[1]上海海事大学海洋科学与工程学院,上海201306 [2]江南造船集团有限公司,上海201913 [3]西北工业大学凝固技术国家重点实验室,西安710072

出　　处：《中国腐蚀与防护学报》2024年第1期47-58,共12页Journal of Chinese Society For Corrosion and Protection

基　　金：国家重点研发计划(2022YFB3705303);上海市科委技术标准项目(21DZ2205700);上海市教委“曙光”计划(19SG46);科技部国际合作交流项目(CU03-29);上海深海材料工程技术中心项目(19DZ2253100)。

摘　　要：为进一步提升高锰钢耐蚀性能,研究了酸性盐雾环境下,Cr、N、Al等微合金化元素添加对全奥氏体高锰钢腐蚀过程和电化学性能的影响。通过失重法、场发射扫描电镜(SEM)、白光干涉仪等手段研究了高锰钢腐蚀产物微观结构及演变规律,并通过动电位极化、交流阻抗谱等电化学技术研究两种高锰钢电化学性能的演化规律。实验结果表明:随着腐蚀时间延长,微合金化高锰钢锈层致密度更高,在长周期腐蚀中具有最好的耐蚀性。盐雾环境中点蚀逐渐发展为均匀腐蚀,微合金化处理后的高锰钢腐蚀动力学规律为ΔW_(WH)=4.44202×10^(-4)t0.9618,小于普通高锰钢的拟合结果ΔW_(PT)=8.74985×10^(-4)t0.67759。电化学结果表明,两种高锰钢腐蚀电流密度随着腐蚀时间增加均逐渐减小,且容抗弧逐渐增大。其中,微合金化高锰钢腐蚀240 h后的容抗弧远远大于未处理高锰钢,且腐蚀速率为1.925×10^(-3)mm/a,小于未处理高锰钢。微合金化处理后的高锰钢耐蚀性能更优,主要原因为Cr、N、Al等元素的微合金化使高锰钢析出碳化物减少,表面生成的氧化物更牢固、致密,提高了高锰钢表面氧化膜的完整性,有效阻碍Cl-渗入,使腐蚀产物变得致密,进而降低钢的腐蚀速率。To further enhance the corrosion resistance of high manganese steel,the effect of adding micro-alloying elements such as Cr,N,and Al on the corrosion process and electrochemical properties of fully austenitic high manganese steel(HMS)in acidic salt spray environment was investigated.The corrosion performance and corrosion products of the HMS were assessed by means of mass loss method,field emission scanning electron microscopy(SEM),and white light interferometry,and the evolution of electrochemical properties of two HMSs(namely the micro-alloyed HMS(WH-HMS)and the un-alloyed HMS(PT-HMS))was examined by electrochemical techniques such as dynamic potential polarization and AC impedance spectroscopy.The results show that with the prolongation of corrosion time,the formed oxide scale on Micro-alloyed HMS becomes much more compact and has much better corrosion resistance for long-cycle corrosion.The corrosion kinetics of the micro-alloyed high Mn steels followsΔW_(WH)=4.44202×10^(-4) t 0.9618,in the contrast,the un-alloyed HMS followsΔW_(PT)=8.74985×10^(-4) t 0.67759.The electrochemical results show that the corrosion current density of the two HMSs gradually decreases with increasing corrosion time,and the capacitive arc gradually increases.After 240 h corrosion,the micro-alloyed HMS presents the capacitive arc much greater than that of the untreated HMS,whereas the corresponding corrosion rate of 1.925×10^(-3) mm/a for the former is less than that of the later.The main reason for the better corrosion resistance of the micro-alloyed high manganese steel is that the micro-alloying of Cr,N,and Al reduces the precipitation of carbides within high manganese steel,the formed oxide scale is much compact with good adhesion to the substrate,therefore which can effectively hinder the attack of Cl-and thus provide better protectiveness for the micro-alloyed HMS.

关 键 词：高锰奥氏体钢 盐雾试验 微合金化 腐蚀速率 电化学测试 

分 类 号：TG174[金属学及工艺—金属表面处理]