磁控溅射类石墨镀层的微观组织观察与分析

利用非平衡磁控溅射系统制备了含微量Cr的类石墨镀层,使用四点探针法测量所制备镀层的电阻率,测试结果表明所制备镀层工作层为类石墨层。使用SEM观察了镀层形貌,使用TEM及HRTEM观察了镀层的微观组织并利用选区电子衍射分析了镀层相结构,观察和分析结果表明:镀层表面质量良好,镀层的纯Cr金属底层为柱状晶结构,过渡层的晶体结构为非晶相中嵌有Cr纳米晶结构;工作层为非晶结构。测定了镀层的硬度、结合力,以及在不同载荷下的摩擦因数和比磨损率,测试结果表明:所制备镀层具有高硬度、高结合力、低摩擦因数和低比磨损率,且高载下比低载下有更低的摩擦因数。分析和讨论的结果还表明:工作层的非晶结构,是使所研究镀层具有高硬度、高结合力、低摩擦因数、低磨损率低的主要原因。

The Microstructure and Analysis of Graphite-like Carbon Film Deposited by Unbalanced Magnetron Sputtering Technique

Graphite-like carbon coatings(GLC)with Cr element were prepared using the unbalanced magnetron sputtering system. The electrical resistivity of coatings were tested by four-point probe method. The results showed that the working layer of the coating was graphite-like carbon layer. Morphology of the coating was observed by SEM. Microstructure and phase structure of the coating were observed and analysed by TEM, HRTEM and selective electronic diffraction, respectively. The results showed that the coating possessed excellent high surface quality, pure Cr sub-layer was columnar crystalline structure. Cr/C transition layer was the structure of Cr nano-crystal embeded in amorphous phase, working layer was amorphous structure. The hardness and adhesion of coating as well as friction coefficient and specific wear rate at different loads were tested. The results showed that the coating presented high hardness, outstanding adhesion strength, low friction coefficient and low specific wear rate. Especially, lower friction coefficient was exhibited at high load not low load. The working layer with amorphous structure was important reason why the coating presented such good properties.