沉积温度对钢球表面含氢碳薄膜结构和摩擦学性能的影响

目前,含有类富勒烯碳结构的氢化碳薄膜(FL-C:H)主要通过等离子体增强化学气相沉积技术(PECVD)在单晶硅表面制备。文中在碳薄膜PECVD沉积工艺之前,通过额外引入原位渗氮方法在钢球表面沉积过渡层以增强薄膜与基材结合力,从而成功制备了具有类富勒烯结构的含氢碳薄膜。通过改变钢球表面碳膜沉积时间(30、60、90、120、150和180 min)获得厚度不同、结构变化的碳膜,进而研究碳膜的结构演变与摩擦学性能之间的关系。结果表明:FL-C:H薄膜PECVD沉积工艺(采用了比额外引入的原位渗氮工艺更低的基底偏压)使钢基底温度随沉积时间增加而下降,导致薄膜结构转变。碳膜结构最初为类石墨结构,随着沉积时间的增长逐渐转变为类富勒烯结构;沉积时间为180 min的碳基薄膜具有超低摩擦因数(0.009)和超长磨损寿命(53 000个周期)。

Effects of Deposition Temperature on Structure and Tribological Properties of Hydrogenated Carbon Films on Steel Balls

Currently, hydrogenated carbon films containing the fullerene-like structures (FL-C:H) are mainly prepared on single-crystal Si substrates by plasma enhanced chemical vapor deposition (PECVD). In-situ plasma nitriding was additionally introduced prior to the PECVD process, to enhance the adhesion between the carbon films and steel substrates. The samples were prepared with different deposition times (30, 60, 90, 120, 150 and 180 min). Thickness, nanostructural evolution and tribological behavior of the coating were investigated. The results show that the FL-C:H film PECVD deposition process causes the temperature of the steel substrate to decrease as the deposition time increases (using a lower substrate bias than the extra in-situ nitriding process introduced), resulting in the structure transformation of the film. The films precent a graphite-like structure at the starting stage and gradually transform into a fullerene-like structure. The films deposited for 180 min exhibit super-low friction (0.009) and superlong wear life (53 000 cycles).