溅射能量对WC/a-C:H薄膜结构与性能的影响

摘要

为探究溅射能量对WC/a-C:H薄膜结构与性能的影响,并讨论WC掺杂对a-C:H薄膜的影响.通过非平衡磁控溅射+等离子体增强化学气相沉积法(UBMS+PACVD),以WC靶作为溅射靶,C2H2为反应气体,通过调制溅射靶电流,在316不锈钢基体上制备WC/a-C:H系列薄膜.用场发射电镜、透射电镜、X射线衍射仪、XPS、拉曼光谱等对薄膜的微观结构和成分进行表征,用划痕仪、纳米硬度仪测试了薄膜的力学性能,用多功能摩擦机对薄膜的摩擦学性能进行分析.结果表明:WC主要以β-WC1?x纳米晶的形式均匀分布在非晶碳中,随着溅射靶电流的上升,薄膜中W含量和膜基结合力呈上升趋势,在11A时上升至21.9%(摩尔分数)和18.6 N,而ID/IG比值和硬度逐渐降低至0.55和11 GPa.溅射靶电流为4 A时,WC/a-C:H薄膜表现出较好的磨损性能,摩擦因数低至0.15,磨损率为5.38×10?7mm3/(N?m).%In order to investigate the influence of sputtering energy on the structure and properties of WC/a-C:H films and discuss the influence of WC doping on a-C:H films, the series of WC/a-C:H films were prepared on 316 stainless steel substrates by modulating the target current with UBMS+PACVD method. The WC target and C2H2were used as the sputtering target and the reaction gas, respectively. The microstructure and composition of the films were characterized by field emission electron microscopy, transmission electron microscopy, X-ray diffraction, XPS and Raman spectroscopy. Scratch tester and nano-hardness tester were used to test the mechanical properties of the films. The tribological properties of the film were analyzed by a trace test system. The results show that WC is mainly distributed in the amorphous carbon in the form of β-WC1?xnanocrystals. With the increase of the sputtering target current, the content of W and the binding force of the film increase to 21.9% (mole fraction) and18.6 N, respectively, while the content of ID/IGand hardness decrease at 0.55 and 11 GPa. When the target current is 4 A, the WC/a-C:H films exhibits good wear performance with a friction coefficient as low as 0.15 and a wear rate of 5.38×10?7mm3/Nm.