摘要
以选区激光熔化(SLM)制备的Fe-Mn-Cr-Ni中熵合金(MEA)为对象,重点研究了打印态和经不同时效温度处理的MEA在1 mol/L NaOH溶液中的耐腐蚀性能,分析了微观组织对腐蚀行为的影响。结果表明,SLM-MEA经过300℃时效后,晶界处的富Cu相优先被溶解,从而抑制了活性部位溶解,提高了耐腐蚀性能。对比打印态,300℃时效态的腐蚀电流下降了37.37%,极化电阻提高了2倍。随着时效温度升高,富Cu析出相的位置沿晶界处向胞状亚晶内部转移。富Cr碳化物随着温度升高发生粗化,削弱了钝化膜的保护能力。此外,300℃时效态中富Cu析出相的溶解,提高了钝化膜中Cr+Ni/Fe+Mn阳离子比,其值为打印态的1.2倍,促进更致密连续的钝化膜形成。
The Cu-containing Fe-Mn-Cr-Ni medium entropy alloy(MEA)was prepared by selective laser melting(SLM)and followed by post aging treatment,and then its microstructure and corrosion performance in 1 mol/L NaOH solution were studied.The results show that the Cu-rich phase at grain boundaries of SLM-MEA is preferentially dissolved after aging at 300℃,which inhibits the dissolution of the active site and improves the corrosion resistance.Compared with the SLM alloy,the corrosion current of the alloy after being aged at 300℃decreased by 37.37%and the polarization resistance increased by 2 times.As the aging temperature increased,the Cu-rich precipitates migrate from grain boundaries to the interior of the cellular sub-crystal.Cr-rich carbides coarsened with the increasing temperature,which weakened the protective ability of the passivation film.In addition,the dissolution of Cu-rich precipitates in the alloy aged at 300℃increased the cation ratio of Cr+Ni to Fe+Mn in the passivation film,which was 1.2 times that of the as prepared SLM alloy,and promoted the formation of a denser and continuous passivation film.
作者
易铄
周生璇
叶鹏
杜晓洁
徐震霖
何宜柱
YI Shuo;ZHOU Shengxuan;YE Peng;DU Xiaojie;XU Zhenlin;HE Yizhu(School of Materials Science and Engineering,Anhui University of Technology,Ma'anshan 243032,China;Anhui Key Laboratory of Materials and Processing,Anhui University of Technology,Ma'anshan 243032,China)
出处
《中国腐蚀与防护学报》
CAS
CSCD
北大核心
2024年第6期1589-1600,共12页
Journal of Chinese Society For Corrosion and Protection
基金
国家自然科学基金(51971001)
安徽省科技重大专项(2022a05020017)。
关键词
中熵合金
选区激光熔化
时效处理
微观组织
腐蚀性能
medium entropy alloy
selective laser melting
aging treatment
microstructure
corrosion resistance
作者简介
易铄,男,1998年生,硕士生;通讯作者:何宜柱,E-mail:heyizhu@ahut.edu.cn,研究方向为金属材料加工。
