摘要
以H13钢为基体材料,采用激光熔覆技术在不同激光能量密度条件下制备了AlCoCrFeNi高熵合金涂层。利用光学显微镜观察了高熵合金涂层的截面形貌和微观组织,通过显微硬度计测量了其显微硬度值,并对显微硬度的Weibull分布特性进行了探讨。结果表明:较低或较高激光能量密度条件下所制备的高熵合金涂层易产生气孔、裂纹等冶金缺陷以及形成粗大的显微组织,当激光能量密度为7.23 kJ/cm^(2)时,可获得表面相对光滑、冶金缺陷少和显微组织明显细化与均化的高熵合金涂层。高熵合金涂层的显微硬度均明显高于基体,激光能量密度为7.23 kJ/cm^(2)下的涂层显微硬度值(540.7 HV)最高,较基体(225 HV)提高约140.3%,在此激光能量密度作用下制备的高熵合金涂层显微硬度Weibull模数为其他激光能量密度下所制备高熵合金涂层的2倍左右,表现出最为集中的显微硬度以及分布更加均匀的显微组织。
AlCoCrFeNi high entropy alloy coating was prepared by laser cladding technology with H13steel as the substrate under different laser energy density.The microstructure and microhardness of high entropy alloy coating were identified by optical microscope and microhardness tester,respectively.Moreover,the Weibull distribution characteristics of microhardness were further studied.Results show that the high entropy alloy coating prepared under the condition of low or high laser energy density is easy to produce metallurgical defects such as pores,cracks and coarsened microstructure.When the laser energy density is 7.23kJ/cm^(2),the high entropy alloy coating with relatively smooth surface,few metallurgical defects and obvious refinement as well as homogenization of microstructure can be obtained.The microhardness of the high entropy alloy coating is significantly higher than that of the substrate.The microhardness value of the coating(540.7HV)is the highest when the laser energy density is 7.23kJ/cm^(2),which is about 140.3%higher than that of the substrate(225HV).The microhardness Weibull modulus of the high entropy alloy coating prepared under the action of this laser energy density is two times than that of the high entropy alloy coating prepared under other laser energy densities,exhibiting the most concentrated microhardness and more evenly distributed microstructure.
作者
徐家乐
胡增荣
王松涛
谭文胜
周建忠
Xu Jiale;Hu Zengrong;Wang Songtao;Tan Wensheng;Zhou Jianzhong(Department of Intelligent Equipment,Changzhou College of Information Technology,Changzhou213164,Jiangsu,China;School of Rail Transportation,Soochow University,Suzhou215131,Jiangsu,China;School of Mechanical Engineering,Jiangsu University,Zhenjiang212013,Jiangsu,China)
出处
《应用激光》
CSCD
北大核心
2023年第7期65-72,共8页
Applied Laser
基金
常州市科技计划项目(CJ20210034)
江苏省高校自然科学研究面上项目(20KJB460016)
常州信息职业技术学院2020年度校级科研平台项目(KYPT202003Z)。
关键词
激光熔覆
激光能量密度
高熵合金涂层
显微组织
显微硬度
laser cladding
laser energy density
high entropy alloy coating
microstructure
microhardness
作者简介
徐家乐(1989-),男,博士,讲师。研究方向为激光熔覆。E-mail:xujiale1989@sina.com。
