等离子体硼氮共渗预处理对硬质合金刀具表面金刚石涂层结合强度的影响  

Adhesion Between Diamond Film and Cemented Carbide Affected by Plasma Boronitriding Pretreatment

作　　者：刘兴龙[1] 王兵[1] 熊鹰[1] 许立[1] 韩汶洪 袁稳[1] 

机构地区：[1]西南科技大学材料科学与工程学院,四川绵阳621010

出　　处：《稀有金属》2016年第5期460-466,共7页Chinese Journal of Rare Metals

基　　金：国家自然科学基金委员会与中国工程物理研究院联合基金项目(U1330127);国家自然科学基金青年科学基金项目(11205127)资助

摘　　要：在硬质合金刀具表面沉积金刚石涂层是提高其切削寿命和切削性能的有效途径,然而在金刚石涂层沉积过程中由于刀具基材中钴催化石墨生长会导致涂层-基体之间结合力差,涂层刀具性能变坏。采用两种等离子体预处理方法(等离子体硼氮共渗预处理、等离子体渗硼预处理)和传统MC试剂预处理方法抑制钴的有害作用,分别从钴的钝化效果、金刚石涂层结构分析、膜-基结合强度分析3个方面进行对比研究。结果表明:等离子体硼氮共渗预处理法在700℃反应温度下渗硼摩尔分数为77.24%,实现了低温高渗硼量,且工艺简单,得到对钴原子的最佳钝化效果,同时通过这种处理的硬质合金刀具表面可制备出光滑、结合力强的纳米金刚石涂层,等离子体硼氮共渗预处理是改善金刚石涂层硬质合金刀具性能的有效手段。To improve the life and performance of tungsten carbide cutting tools, applying diamond coating on their surface is a new and useful approach, while the most difficult obstacle lies in the existence of cobalt in the cemented carbide substrate which would catalyze the growth of graphite between coating and substrate, and weakening their adhesion. To overcome this problem, two plasma pretreatment methods （plasma boronitriding pretreatment, plasma boronizing pretreatment） and a typical traditional pretreatment method （MC-pretreatment） were applied to attenuate the adverse effect of cobalt. Three aspects including the passivating effect for cobalt, structure of diamond coating, film-substrate bonding strength correlated with different pretreatments were researched relatively. The results indicated that for the plasma boronitriding pretreatment methods, high boron-doped amount of 77.24% and the best cobalt-fastened effect could be obtained at low temperature of 700 ℃ in relatively simple process. Furthermore, the smooth and hard bonding nano-crystalline diamond coating on the pretreated substrate could be prepared for better usability, which proved that the plasma boroni-triding pretreatment was an effective approach for improving the adhesion between diamond coating and cemented carbide substrate.

关 键 词：MPCVD 等离子体硼氮共渗预处理法 纳米金刚石膜 硬质合金 

分 类 号：TG7[金属学及工艺—刀具与模具]