AC-HVAF喷涂纳米结构WC-12Co耐磨涂层的微观结构和性能（英文）  

Microstructures and Properties of Nano-structural WC-12Co Coatings Deposited by AC-HVAF

作　　者：樊自拴[1] 王山松[1] 张正东[1] 

机构地区：[1]北京科技大学,北京100083

出　　处：《稀有金属材料与工程》2017年第4期923-927,共5页Rare Metal Materials and Engineering

摘　　要：采用含纳米WC颗粒的WC-12Co粉末,通过空气助燃超音速火焰喷涂系统(AC-HVAF)制备了耐磨涂层。研究了涂层相组成、微观结构、涂层硬度、断裂韧性和耐磨损性能。X射线衍射分析结果表明WC为涂层主相,未发现其他失碳分解产物。涂层孔隙率低于1%,晶粒尺寸为80~100 nm,涂层磨光表面硬度(HV_(0.3))高达19 403 MPa,横截面硬度高达17 410 MPa。使用WC硬质球为摩擦副,载荷15 N,工件转速1198 r/min干磨条件下,纳米结构涂层的平均失重比微米结构涂层降低40%,且纳米结构涂层摩擦系数为0.26~0.28(微米结构涂层:0.25~0.4),因此纳米结构涂层具有更加优异的耐磨性能。WC-12Co powder with nano WC grains was used to deposit wear resistant coatings by AC-HVAF （acukote high velocity air-fuel） spray system. The phase compositions and micmstructures of the coatings were examined. The microhardness, fracture toughness and wear resistance were investigated. According to the X-ray diffraction （XRD） analysis, the principal phase is WC, and its decomposition products are not found. The sprayed coating has a porosity lower than 1% and the grain sizes of coatings are among 80-100 nm which contribute to an average microhardness （HV0.3） as high as 19 403 MPa on the surface and 17 410 MPa on the cross-section. At the load of 15 N and rotational speed of 1198 r/min of WC counter body, the nano-sized coatings show a decreased average mass loss by 40% compared with micro-sized coatings, and a stable friction coefficient of 0.26-0.28 （micron-sized coatings： 0.25-0.4 ） in the dry wear conditions. It is concluded that the sprayed nano structural WC-12Co coatings have a better wear resistance.

关 键 词：AC-HVAF 纳米WC 显微硬度 耐磨 

分 类 号：TG174.4[金属学及工艺—金属表面处理]