颗粒粒径对碳化钨/高强钢复合材料界面微观组织和元素扩散的影响  

Effect of WC particle size on microstructure and diffusion at the interface of WC/HSS composites

作　　者：李刚 张红梅[1,2] 赵大东 王超 李洪楠 李娜 孟令浩[1] 姜正义 LI Gang;ZHANG Hongmei;ZHAO Dadong;WANG Chao;LI Hongnan;LI Na;MENG Linghao;JIANG Zhengyi(College of Materials and Metallurgy, University of Science and Technology Liaoning,Anshan 114051, China;State Key Laboratory of Metallic Materials for Marine Equipment and Their Applications,Anshan 114051, China;Technology Research Institute of Benxi Steel Group, Benxi 117000, China;School of Mechanical, Materials and Mechtronic Engineering, University of Wollongong,Wollongong 2522, Australia)

机构地区：[1]辽宁科技大学材料与冶金学院,辽宁鞍山114051 [2]海洋装备用金属材料及其应用国家重点实验室,辽宁鞍山114051 [3]本钢集团技术研究院,辽宁本溪117000 [4]澳大利亚伍伦贡大学机械、材料和机电一体化学院,澳大利亚伍伦贡NSW2522

出　　处：《功能材料》2021年第1期1104-1114,共11页Journal of Functional Materials

基　　金：国家自然科学基金面上资助项目(51474127,51671100);辽宁科技大学材料与冶金学院船舶装备与应用金属材料国家重点实验室联合资助项目(SKLMEA-USTL 2017010和201905)。

摘　　要：利用“冷压成型-真空烧结法”制备了碳化钨/高强钢复合材料。结合光学显微镜、扫描电镜、超高温激光共聚焦显微镜和显微硬度计等分析测试手段对不同碳化钨(WC)颗粒粒径下获得的复合材料以及界面的显微组织和硬度进行了分析。实验结果表明,WC粉末颗粒粒径越小,WC平均晶粒尺寸越小;同时,WC致密度越高,当WC粉末颗粒粒径为100 nm,致密度达到91.22%;WC粉末颗粒粒径越小,复合材料中WC一侧的硬度越高。当WC粉末颗粒粒径为100 nm,烧结温度为1320℃时,WC最高硬度值达1680HV0.1左右;且在靠近结合界面处WC硬度较其他位置更高;芯部的高速钢材料随WC颗粒粒径的变化不大,都在500HV0.1左右。当WC粉末颗粒粒径为200 nm时,碳化钨与高强钢在界面处形成了一定宽度的过渡层,复合材料的结合为冶金结合;高强钢基体中的铁元素扩散到接触的碳化钨组织中,产生了一定宽度的熔合层,复合材料界面结合相对较好。在过渡区域内,W、Fe和Co元素在界面处都发生了明显的扩散;随着碳化钨颗粒粒径的增大,元素扩散趋势减弱。当WC粉末颗粒粒径为500 nm时,在复合材料界面处Fe元素和W元素未发生明显扩散现象,只有Co元素发生了一定程度的扩散。Tungsten carbide/high strength steel(WC/HSS)composites were prepared by cold pressing and vacuum sintering.The microstructure and micro-hardness of the composites with different particle sizes were analyzed by optical microscopy(OM),scanning electron microscopy(SEM),ultra-high temperature laser confocal microscope and microhardness tester.The results show that WC density tended to increase as the average grain size of WC decreased.When the particle size of WC powder was 100 nm,the density reached 91.22%.The micro-hardness of WC increased with the decrease of WC particle size.When the particle size of WC powder was 100 nm and sintering temperature was 1320℃,the micro-hardness of WC reached about 1680 HV0.1.The micro-hardness of WC near the bonding interface was higher than that of other parts.The microhardness of HSS core varied little with WC particle size,which was about 500 HV0.1.When the particle size of WC powder particles was 200 nm,a transition layer with a certain width was formed at the interface between WC and HSS,and the combination between the two materials was metallurgical.The iron element in the HSS matrix diffused into WC structure contacted with it,resulting in a certain width of a fusion layer,and the composite interface was relatively well bonded.When the average particle size of WC powder was 200 nm,W,Fe and Co elements significantly diffused in the transition zone at the interface.With the increase of WC particle size,the trend of elements diffusion decreased.When the particle size of WC powder particles was 500 nm,no obvious diffusion of Fe and W elements occurred at the interface of the composite,but only a certain degree of diffusion of Co element occurred.

关 键 词：复合材料 微观组织 界面 粒径 

分 类 号：TB333[一般工业技术—材料科学与工程]