12CrMoV合金钢表面激光熔覆WC/Ni基涂层组织演变及性能研究  

Microstructure Evolution and Properties of WC/Ni Based Coating on the Surface of 12CrMoV Alloy Steel by Laser Cladding

作　　者：韩基泰 夏庆锋 王可庆 花国祥 Han Jitai;Xia Qingfeng;Wang Keqing;Hua Guoxiang(School of Automation,Wuxi University,Wuxi 214105,Jiangsu,China)

机构地区：[1]无锡学院自动化学院,江苏无锡214105

出　　处：《激光与光电子学进展》2024年第9期342-349,共8页Laser & Optoelectronics Progress

基　　金：辽宁省科技厅联合开放基金-机器人学国家重点实验室开放基金(2021-KF-22-19);江苏省高等学校基础科学(自然科学)面上项目(21KJB480012);无锡市科技发展资金(K20221051)。

摘　　要：为解决冷作模具钢在长期服役过程中易发生磨损失效及腐蚀失效的问题,利用激光熔覆技术在12CrMoV基板上制备了不同WC含量的Ni60涂层。利用X射线衍射仪、扫描电子显微镜、X射线能谱仪、摩擦磨损试验机及电化学工作站对涂层的成形特征、显微组织、力学性能及耐腐蚀性能进行了表征。结果表明:WC的添加量改变了熔池的凝固特性,从而降低了涂层的宽度,提高了涂层的深度;当WC的添加量为30%(质量分数)时,涂层的硬度为853 HV0.3,平均摩擦因数仅为0.467,具有优异的力学性能,但韧性降低,导致凝固过程中形成孔隙,降低了涂层的耐腐蚀性能;当WC的添加量为10%和20%时,晶粒组织的尺寸得到了细化,晶界面积减小,具有优异的耐腐蚀性能;当WC添加量为20%时,涂层的腐蚀电流密度仅为3.65×10-5A/cm^(2),并且力学性能略低于WC添加量30%得到的涂层。因此,探究了适用于磨损环境及腐蚀环境的WC/Ni60涂层,确定了WC的最佳添加量,拓展了WC/Ni60涂层在模具钢的应用范围,对工程实践具有指导意义。To solve the problems of wear and corrosion failure in coldworking die steel during longterm service,Ni60 coatings with different WC contents are prepared on 12CrMoV substrate using laser cladding technology.The forming characteristics,microstructure,mechanical properties,and corrosion resistance of the coatings are characterized using Xray diffraction,scanning electron microscopy,energy dispersive spectroscopy,friction and wear testing machines,and electrochemical workstations.The results indicate that the additive amount of the WC can change the solidification characteristics of the melt pool,thereby reducing the width of the coatings and increasing the depth of the coatings.When the additive amount of the WC is 30%(mass fraction),the hardness of the coating is 853 HV0.3,and the average friction coefficient is only 0.467.It has excellent mechanical properties,but the toughness of the coating decreases,leading to the formation of pores during the solidification process,which reduces the corrosion resistance of the coating.When the additive amount of the WC is 10%and 20%respectively,the size of the grain structure is refined,the grain boundary area is reduced,and it has excellent corrosion resistance.When the additive amount of the WC is 20%,the corrosion current density of the coating is only 3.65×10−5 A/cm^(2),and the mechanical properties are only slightly lower than the coating obtained with 30%WC additions.Therefore,this study explored suitable WC/Ni60 coatings for wear and corrosion environments,determined the optimal additive amount of the WC,expanded the application range of WC/Ni60 coatings in mold steel,and has guiding significance for engineering practice.

关 键 词：模具钢 激光熔覆 WC/Ni60涂层 显微组织 性能表征 

分 类 号：TN249[电子电信—物理电子学]