电子束重熔对机械合金化法制备TiC/Ti复合涂层组织及摩擦性能的影响  

Effect of electron beam remelting on microstructure and tribological properties of TiC/Ti composite coating prepared by mechanical alloying

作　　者：方超 姚正军[1,2] 张莎莎 陶学伟 刘莹莹[1] FANG Chao;YAO Zhengjun;ZHANG Shasha;TAO Xuewei;LIU Yingying(College of Material Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China;Key Laboratory of Materials Preparation and Protection for Harsh Environment,Ministry of Industry and Information Technology,Nanjing 211106,China)

机构地区：[1]南京航空航天大学材料科学与技术学院,南京211106 [2]面向苛刻环境的材料制备与防护技术工业和信息化部重点实验室,南京211106

出　　处：《复合材料学报》2019年第1期167-177,共11页Acta Materiae Compositae Sinica

基　　金：江苏省"六大人才高峰"第十二批高层次人才资助项目(YPC16005-PT);江苏高校优势学科建设工程资助项目

摘　　要：对机械合金化(MA)法制备的TiC/Ti复合涂层进行电子束重熔处理,分析了经过不同电子束扫描速度的重熔工艺后TiC/Ti复合涂层组织和耐磨性能的变化规律。结果表明,当扫描速度为5～15mm/s时,重熔处理消除了MA法制备的TiC/Ti复合涂层中的孔隙和裂纹,使其硬度与耐磨性能显著提高;但扫描速度过快(20mm/s)时,TiC/Ti复合涂层内部出现重熔导致的孔洞缺陷。随着扫描速度由5mm/s增加至15mm/s,重熔后TiC/Ti复合涂层中的TiC相由粗大树枝状晶体逐渐转变为弥散分布的短棒和颗粒状晶体,弥散强化作用和固溶强化作用逐渐增强,TiC/Ti复合涂层的硬度由重熔前HV 554逐渐提高至HV 783,磨损速率由5.93×10-4mm3(N·m)-1逐渐下降至1.75×10-4 mm3(N·m)-1,扫描速度为15mm/s重熔后TiC/Ti复合涂层的性能最佳。An electron beam was applied to remelt TiC/Ti composite coating prepared by mechanical alloying(MA)method.The microstructure and wear resistance of the coatings were analyzed after electron beam remelting with different scanning velocities.The results show that when the scanning velocity is between 5 mm/s and 15 mm/s,the hardness and wear resistance of TiC/Ti composite coatings are significantly improved due to elimination of the pores and cracks through remelting process.Remelting defects appear inside the coating when the scanning velocity is too fast(20 mm/s).With the increase of scanning velocity from 5 mm/s to 15 mm/s,TiC phase in the TiC/Ti compos-ite coating changes from coarse dendritic crystals to short rod-like and granular crystals gradually,enhancing the dis-persion strengthening effect and solid solution strengthening effect.The hardness of TiC/Ti composite coatings in-crease from HV 554(before remelting)to H V 783,and the wear rate of the coating decreases from 5.93×10^-4 mm^3(N·m)^-1 to 1.75×10^-4 mm^3(N·m)^-1 with the increase of scanning velocity.The remelted TiC/Ti composite coating reaches the best performance at the scanning velocity of 15 mm/s.

关 键 词：TIC/TI 复合涂层 电子束重熔 机械合金化 耐磨性能 

分 类 号：TB331[一般工业技术—材料科学与工程]