不同颗粒度碳化钨的WC-17Co等离子涂层组织及摩擦学特性研究

Research on Different Particle Size of Tungsten Carbide on Organization and the Tribological Characteristics of Plasma Sprayed WC-17Co Coating

选取0.8μm、1.5μm、3.5μm三种WC颗粒度的WC-17Co复合粉末,采用等离子喷涂工艺在Q235钢表面制备了涂层。通过扫描电镜、显微硬度仪对3种粉末及其涂层的本征性能进行了测定及分析,利用滑动磨损试验研究了涂层磨粒磨损性能。结果表明:等离子喷涂过程中,原始颗粒度更大的WC在喷涂过程中较难分解,3.5μm-WC的涂层中WC颗粒形貌更为完整。颗粒度越大,涂层的显微硬度更高,且各向同性表现更好,3.5μm-WC的表面显微硬度为1124.7,截面显微硬度达到1163.7。抗磨粒磨损性能也更为优异,3.5μm-WC的涂层摩擦系数在最短的时间到达稳态,摩擦系数最低,为0.546,涂层磨粒磨损量最少,仅为0.5mg。

Selecting 0.8μm,1.5μm,3.5μm three kinds of particle size of WC,and preparing of WC-17 Co composite powder. By scanning electron microscope and microhardness tester,the intrinsic properties of these powders and the coating were determined and analyzed. The sliding wear test was used to study the abrasive wear performance of the coating. Results show that the plasma spraying process,the greater particle size WC is more difficult to decompose in the process of spraying,the WC particles of WC-17 Co coating of 3.5μm WC is more complete. The greater particle size is,the better microhardness and isotropic are. The surface microhardness of WC-17 Co coating of 3.5μm WC is 1124.7,and the cross-section microhardness reaches 1163.7. The coating of 3.5μm-WC reach steady state friction coefficient in the shortest time,the friction coefficient is 0.546,coating of abrasive wear is the least,only 0.5 mg. So the abrasion wear is more excellent performance than others.