强流脉冲电子束改性石墨/硬质合金自润滑涂层性能  

Properties of graphite/cemented carbide self-lubricating coating modified by high current pulsed electron beam

作　　者：张悦[1] 郑钰 何星池 陈飞 董福宇[1] ZHANG Yue;ZHENG Yu;HE Xingchi;CHEN Fei;DONG Fuyu(School of Materials Science and Engineering,Shenyang University of Technology,Shenyang 110870,Liaoning,China)

机构地区：[1]沈阳工业大学材料科学与工程学院,辽宁沈阳110870

出　　处：《沈阳工业大学学报》2025年第1期53-60,共8页Journal of Shenyang University of Technology

基　　金：辽宁省自然科学基金材料联合基金项目(2021-KF-15-01)。

摘　　要：【目的】硬质合金是一种以微米级难熔金属化合物(WC、TaC、TiC、NbC)粉末为硬质相,以过渡族金属(Co、Fe、Ni)粉末为烧结黏结相,经高温烧结制备而成的合金。硬质合金因具有高硬度、高强度、耐磨耐腐蚀性和良好高温性能,被广泛应用于刀具材料等工业领域,被称为“工业牙齿”。随着我国战略性新兴产业的发展,航空航天、海洋工程、数控机床、轨道交通、核工程、新能源、先进医疗装备、环保节能装备等高端制造产业对高性能高稳定性刀具材料的需求越来越大。采用涂层镀膜等表面处理方法将固体润滑剂涂覆在刀具表面,或将固体润滑剂作为添加剂加入刀具材料基体,利用固体润滑剂高温稳定的优点,在服役刀具表面形成连续的固态润滑层,有利于刀具性能的进一步提升。【方法】以WC-Co硬质合金粉末(粒径15~45μm)为耐磨组元,以石墨粉末(粒径80~200μm)为固体润滑剂,通过球磨法制备球形复合粉末,采用等离子喷涂工艺将复合粉末沉积为石墨/WC-Co涂层,采用强流脉冲电子束(能量密度27 keV、脉冲间隔15 s)进行辐照处理,辐照次数为1、10、20和30。对处理后涂层的显微组织和力学性能进行观察。【结果】采用强流脉冲电子束处理后,重熔涂层表面致密平整,改性层厚度可达294μm,表面硬度最高可达800 HV,平均摩擦系数最低可降至0.10。显微结构分析表明,强流脉冲电子束辐照后涂层表面生成纳米尺寸的WC相、Co_(3)W_(9)C_(4)相和类金刚石结构,使涂层表面显微硬度大幅提高;电子束使涂层表面大块石墨溶解后重新析出,生成椭球状石墨,同时石墨在电子束作用下分离成石墨烯片层,均匀覆盖在涂层表面,有效降低了涂层表面的摩擦系数;部分石墨转变为金刚石结构,有效提升了涂层的表面硬度。【结论】采用热喷涂沉积和强流脉冲电子束改性的两步技术,制备了表面均匀、致[Objective]Cemented carbides are a class of alloy prepared by high-temperature sintering in which micron-scale refractory metal compound(WC,TaC,TiC,and NbC)powder is taken as the hard phase and the transition metal(Co,Fe,and Ni)powder as the sintering bonding phase.They are widely used in tool materials and other industrial fields,known as“industrial teeth”,due to their high hardness,high strength,wear resistance,corrosion resistance,and good high temperature performance.With the development of China′s strategic emerging industries,aerospace,marine engineering,CNC machine tools,rail transit,nuclear engineering,new energy,advanced medical equipment,environmentally-friendly and energy-saving equipment,and other high-end manufacturing industries have an increasing demand for high-performance and high-stability tool materials.Tool performance can be further enhanced by the use of coating and other surface treatment methods to coat the solid lubricant on the tool surface,or the addition of the solid lubricant as an additive to the tool material matrix,which leverages the advantage of high temperature stability of solid lubricants to form a continuous solid lubrication layer on the service tool surface.[Methods]In this study,spherical composite powder was prepared by ball milling using WC-Co cemented carbide powder(particle size 15-45μm)as wear-resistant component and graphite powder(particle size 80-200μm)as the solid lubricant.The composite powder was deposited to be graphite/WC-Co coating by plasma spraying process.A high current pulsed electron beam(energy density 27 keV,pulse interval 15 s)was used for irradiation treatment,with number of irradiation times set as 1,10,20,and 30.The microstructure and mechanical properties after treatment were observed.[Results]After treatment with the high current pulsed electron beam,the surface of the remelted coating is compact and flat,with a modified layer thickness reaching 294μm,the highest surface hardness can reach 800 HV,an average friction coefficient as low as

关 键 词：强流脉冲电子束 石墨/硬质合金涂层 石墨烯 金刚石 耐磨性能 显微组织 相组成 摩擦磨损性能 

分 类 号：TG135[一般工业技术—材料科学与工程]