激光熔覆FeCoCrNiMo_(x)高熵合金涂层的组织和电化学腐蚀行为  

Microstructure and Electrochemical Corrosion Behavior of Laser Cladding FeCoCrNiMo_(x)High Entropy Alloy Coatings

作　　者：刘弘 陈勇[1] 周娟[1] 张世钦 朱永刚 焦少彬 Liu Hong;Chen Yong;Zhou Juan;Zhang Shiqin;Zhu Yonggang;Jiao Shaobing(College of Mechanical Engineering,University of South China,Hengyang,Hunan 421001,China;Xiangtan Branch Hunan Special Equipment Inspection and Testing Institute,Xiangtan,Hunan 411100,China)

机构地区：[1]南华大学机械工程学院,湖南衡阳421001 [2]湖南省特种设备检验检测研究院湘潭分院,湖南湘潭411100

出　　处：《机电工程技术》2023年第2期106-108,200,共4页Mechanical & Electrical Engineering Technology

基　　金：金属矿山安全与健康国家重点实验室项目(编号:2019-JSKSSYS-009);湖南省市场监督管理局科技计划项目(编号:2022KJJH01);湖南省大学生创新创业训练计划项目(编号:210XCX233)。

摘　　要：采用同步送粉激光熔覆技术在27SiMn钢基体表面制备了FeCoCrNiMo_(x)高熵合金涂层,研究了Mo元素含量对FeCoCrNiMo涂层组织的影响。通过X射线衍射仪(XRD)、光学显微镜、扫描电镜(SEM)以及显微硬度计对熔覆层的微观组织结构和显微硬度进行观察和测试,且利用电化学工作站研究了熔覆层电化学腐蚀行为。研究结果表明:高熵合金涂层与基体贴合紧密,形成了良好的冶金结合。FeCoCrNiMo_(0.25)、FeCoCrNiMo0.5高熵合金涂层主要由fcc相和σ相组成,涂层微观组织主要为柱状树枝晶,枝晶间富集Cr、Mo元素。FeCoCrNiMo_(0.25)高熵合金涂层在3.5%NaCl溶液呈现出明显的钝化行为,自腐蚀电流密度为7.84×10^(-7)A/cm^(2),显著优于基体材料,涂层表现出优异的耐腐蚀性能。FeCoCrNiMo_(x)high entropy alloy coating was prepared on 27 SiMn steel by synchronous powder feeding laser cladding technology The effect of Mo content on the microstructure of FeCoCrNiMo coating was studied.X-ray diffractometer(XRD),optical microscope,scanning electron microscope(SEM)and microhardness tester were used to observe and test the microstructure and microhardness of the cladding layer and electrochemical workstation was used to study the electrochemical corrosion behavior of the cladding layer.The results show that the high entropy alloy coating is closely bonded to the substrate,forming a good metallurgical bond.The high entropy coating of FeCoCrNiMo_(0.25)and FeCoCrNiMo0.5alloys is mainly composed of fcc phase andσphase,and the microstructure of the coating is mainly columnar dendrite,with Cr and Mo elements enriched among dendrites.FeCoCrNiMo_(0.25)high entropy alloy coating in 3.5%NaCl solution shows obvious passivation behavior,and the self-corrosion current density is 7.84×10^(-7)A/cm^(2),which is significantly better than the matrix material,and the coating shows excellent corrosion resistance.

关 键 词：高熵合金 耐蚀性能 涂层微观组织 交流阻抗谱 

分 类 号：TG172[金属学及工艺—金属表面处理]