激光选区熔化Inconel 625合金在酸性环境中的腐蚀机理研究  

Investigation on the Corrosion Mechanism of Inconel 625 Alloy by Selective Laser Melting in Acidic Environment

作　　者：韩炬 王博超 董东东 马汝成 龙海洋 李晓硕 王涛 闫星辰 HAN Ju;WANG Bochao;DONG Dongdong;MA Rucheng;LONG Haiyang;LI Xiaoshuo;WANG Tao;YAN Xingchen(College of Mechanical Engineering,North China University of Science and Technology,Tangshan 063210,Hebei,China;Guangdong-Hong Kong Joint Laboratory of Modern Surface Engineering Technology,Guangdong Provincial Key Laboratory of Modern Surface Engineering Technology,Institute of New Materials,Guangdong Academy of Sciences,Guangzhou 510650,China)

机构地区：[1]华北理工大学机械工程学院,河北唐山063210 [2]广东省科学院新材料研究所,粤港现代表面工程技术联合实验室,广东省现代表面工程技术重点实验室,广州510650

出　　处：《材料导报》2025年第10期166-171,共6页Materials Reports

基　　金：中法平台项目(2023YFE0108000);广东省科技计划项目资助(2023B1212120008;2023B1212060045);广东省科学院科技合作平台建设资金(2022GDASZH-2022010203-003);广州市“青年科技人才托举工程”(QT-2023-038);唐山市应用基础研究项目(22130219G);广东省基础与应用研究基金项目(2024A151501102)。

摘　　要：研究了激光选区熔化成形的Inconel 625合金在硫酸和硝酸混合溶液(以下统称混酸)中的腐蚀机理以及粗糙度对其腐蚀速率的影响。通过激光选区熔化(SLM)技术制备Inconel 625原始样品,然后对部分样品的六个面进行抛光,将抛光样品和原始样品在50℃混酸溶液中分别浸泡腐蚀120 h、240 h、480 h、840 h、1080 h。结果表明,样品经混酸溶液浸泡后,首先在晶间产生局部点蚀,在熔池边缘处点蚀的密度更高。随着浸泡时间的延长,点蚀逐渐蔓延至整个样品晶间并逐渐腐蚀进入晶粒中。抛光样品的整体平均腐蚀速率为2.80×10^(-3)mm/a,原始样品的整体平均腐蚀速率为12.70×10^(-3)mm/a,是抛光样品的近5倍,说明粗糙度对腐蚀速率有极大的影响,样品粗糙度越大导致其与混酸接触的面积越大,腐蚀速率越快。Corrosion mechanism of Inconel 625 alloy fabricated by selective laser melting was investigated in a mixed acid(a mixed solution of sulfuric acid and nitric acid).Meanwhile,for Inconel 625 alloy,the effect of roughness on corrosion rate was investigated.The original and polished samples of Inconel 625 fabricated by selective laser melting(SLM)were immersed in a mixed acid at 50℃ for 120 h,240 h,480 h,840 h and 1080 h,respectively.The results show that the corrosion type of the alloy is pitting corrosion,which is first generated between the alloy grains,and the pitting density at the edge of the alloy molten pool was higher.With the increase of corrosion time,the entire grain boundary was gradually corroded,and pitting corrosion occurs inside the grain.The overall average corrosion rate of the polished sample was 2.80×10^(-3)mm/a,and the original sample was 12.70×10^(-3)mm/a,which was nearly 5 times that of the polished sample.It showed that roughness has a great influence on the corrosion rate,and the higher the roughness of the sample,the larger the contact area with the mixed acid,and the faster the corrosion rate.

关 键 词：激光选区熔化 Inconel 625 耐腐蚀性 粗糙度 腐蚀机理 

分 类 号：TG174.3[金属学及工艺—金属表面处理]