磁场辅助激光熔覆5CrNiMo/Ni60涂层组织微结构及性能研究  

Study on Microstructure and Properties of Magnetic Field Assisted Laser Cladding 5CrNiMo/Ni60 Coating

作　　者：曹阳[1,2] 姚宏凯 吴国庆 王健 朱维南 CAO Yang;YAO Hongkai;WU Guoqing;WANG Jian;ZHU Weinan(School of Mechanical Engineering,Nantong University,Nantong 226019,China;Jiangsu Engineering Research Center of Wind Energy Application,Nantong 226019,China;Nantong Institute of Technology,Nantong 226002,China)

机构地区：[1]南通大学机械工程学院,江苏南通226019 [2]江苏省风能应用技术工程中心,江苏南通226019 [3]南通理工学院,江苏南通226002

出　　处：《南通大学学报（自然科学版）》2020年第4期57-62,共6页Journal of Nantong University(Natural Science Edition)　

基　　金：国家自然科学基金项目(51376096);“十三五”江苏省一级学科省重点建设学科项目(2016-0802机械工程);南通市基础科学研究计划项目(JCZ18019)。

摘　　要：研究了磁场辅助激光熔覆5CrNiMo/Ni60涂层组织微结构及性能的影响。将被熔覆试样置于磁极中间,采用交流电激磁方法,在激光熔覆过程中施加不同磁场强度。结果表明:不同磁场强度下,5CrNiMo合金熔覆层组织主要由CrB2、Cr3B2、Cr7C3及γ-Ni等物相组成;随着磁场强度增大,熔覆层组织上部的胞状晶粒Feret直径和晶粒所占面积分数逐渐变小,中下部从柱状晶向树枝晶转变,熔覆层组织逐渐细化,表面硬度和抗磨损性能逐渐增大,摩擦系数逐渐减小;当磁场强度为30 mT时,熔覆层的平均摩擦系数仅为0.25,显微硬度高达1404 HV0.2,涂层具有较佳的耐磨性能。电磁场辅助激光熔覆技术显著提高了Ni60涂层的耐磨性能,为机械设备关键零件磨损快速修复提供了技术支撑。The effect of different magnetic field on the microstructure and properties of the coating are studied.The cladding sample is placed in the middle of the magnetic poles,and different magnetic field strengths are applied during the laser cladding process by using an alternating current excitation magnetic field method.The results show that the microstructure of 5CrNiMo alloy cladding layer is mainly composed of CrB2,Cr3B2,Cr7C3 andγ-Ni.With the increase of magnetic induction strength,the ferret diameter and the area fraction of the cellular grains in the upper part of the cladding structure gradually decrease,the transition from the columnar crystal to the dendrite in the middle and lower part of the cladding structure gradually refines,the surface hardness and wear resistance gradually increase,and the friction coefficient gradually decreases.When the magnetic induction strength is 30 mT,the average friction coefficient of the cladding layer is only 0.25,the microhardness is as high as 1404 HV0.2,and the coating has the best wear resistance.The technology of magnetic field-assisted laser cladding significantly improves the wear resistance of Ni60 coatings,and provides technical support for the rapid repair of key parts of mechanical equipment.

关 键 词：激光熔覆 电磁场 NI60涂层 显微组织 耐磨性 

分 类 号：TG174.44[金属学及工艺—金属表面处理]