强流脉冲电子束作用下CrFeCoNiMo0.2高熵合金微观结构变化与耐蚀性能研究  

Microstructure Modification and Corrosion Resistance of CrFeCoNiMo0.2 High Entropy Alloy Induced by High-current Pulsed Electron Beam

作　　者：陈亚楠 吕鹏[1] 张舒窈 张从林 蔡杰[2] 李玉新[4] 关庆丰[1] CHEN Ya-nan;LYU Peng;ZHANG Shu-yao;ZHANG Cong-lin;CAI Jie;LI Yu-xin;GUAN Qing-feng(School of Materials Science and Engineering,Jiangsu University,Zhenjiang 212013,Chin;Engineering Institute of Advanced Manufacturing and Modern Equipment Technology,Jiangsu University,Zhenjiang 212013,China;School of Maerials Science and Engineering,Yancheng Institute of Technology,Yancheng 224051,China;School of Material Science and Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013 [2]江苏大学先进制造与现代装备技术工程研究院,江苏镇江212013 [3]盐城工学院材料科学与工程学院,江苏盐城224051 [4]中北大学材料科学与工程学院,山西太原030051

出　　处：《表面技术》2020年第10期214-223,共10页Surface Technology

基　　金：国家自然科学基金(No.51601071);国家自然科学基金-山西煤基低碳联合基金(U1810112);江苏大学青年英才培育计划项目;江苏省博士后科研资助计划(No.2018K025B);江苏省研究生科研实践创新项目(No.KYCX18-2236)。

摘　　要：目的提高CrFeCoNiMo0.2高熵合金的耐腐蚀性能。方法采用强流脉冲电子束(HCPEB)辐照非等原子比CrFeCoNiMo0.2高熵合金(HEA)表面。通过X射线衍射仪(XRD)和扫描电子显微镜(SEM)分析了辐照表面的微观结构和腐蚀形貌。利用CHI760C电化学工作站,在质量分数为3.5%的NaCl溶液中,研究HCPEB辐照处理前后合金的抗腐蚀性能。结果XRD分析表明,辐照样品表面发生了明显的取向变化,在(200)晶面上表现出择优取向。微观结构观察表明,在HCPEB辐照后,合金表面发生重熔,形成熔坑和厚度约为3~5μm的致密重熔层。随着脉冲数量的增加,凹坑的密度和尺寸明显减小。此外,HCPEB处理消除了烧结合金中的孔隙和成分偏析,实现了组织和成分的均匀化。动电位极化曲线表明,与烧结样品相比,辐照样品在3.5%(质量分数)的NaCl溶液中具有更正的腐蚀电位和更低的腐蚀电流密度。Nyquist和Bode图的结果表明,在HCPEB辐照后,样品表面具有良好的电容行为和耐腐蚀性,其中辐照次数为30次时,样品的耐腐蚀性能最好。结论HCPEB消除了烧结合金表面的组织缺陷,促使表面的元素分布更加均匀,进而提高了CrFeCoNiMo0.2高熵合金的耐腐蚀性能。The work aims to improve the corrosion resistance of CrFeCoNiMo0.2 high entropy alloy.The surface of non-equiatomic CrFeCoNiMo0.2 high entropy alloy(HEA)was irradiated by high-current pulsed electron beam(HCPEB).Microstructure and corrosion resistance of the CrFeCoNiMo0.2 HEA before and after high-current pulsed electron beam(HCPEB)irradiation were studied systematically.The microstructure evolution and corrosion morphology of the irradiated surface were analyzed by X-ray diffraction(XRD)and scanning electron microscope(SEM).Corrosion resistance of alloy before and after HCPEB irradiation was studied by CHI760C electrochemical workstation in 3.5 wt.%NaCl solution.The results of XRD analysis indicated that the surface of the irradiated sample exhibited preferential orientation on(200)crystal plane.Microstructure observations revealed that caters and a compact remelted layer with a thickness of about 3~5μm were formed on the surface of the alloy after HCPEB irradiation.The density and size of craters formed on the irradiated surface were significantly decreased with the increasing number of pulses.Besides,the HCPEB treatment eliminated porosity and composition segregation of the sintered alloy,thereby achieving homogeneity of structure and composition.The potentiodynamic polarization curves demonstrated that all the irradiated samples had a positive potential and a lower current density in 3.5%NaCl solution compared with the initial sample.The results of Nyquist and Bode plots showed that the surface of the irradiated samples had better capacitive behavior and corrosion resistance,among which 30-pulsed samples possessed the best corrosion resistance.HCPEB irradiation eliminates the structural defects on the surface of sintered alloy,promotes the more uniform distribution of surface elements,and further improves the corrosion resistance of CrFeCoNiMo0.2 high entropy alloy.

关 键 词：CrFeCoNiMo0.2高熵合金 强流脉冲电子束(HCPEB) 物相组成 微观改性 耐蚀性 腐蚀机理 

分 类 号：TG174.3[金属学及工艺—金属表面处理]