含氢无定型碳摩擦转移膜结构演化规律研究

Structural Evolution of the Transfer Film of a-C:H

利用中频磁控溅射系统制备a-C:H润滑薄膜,并使用球-盘摩擦机考察了空气和干燥氮气(N_(2))氛围中a-C:H薄膜摩擦行为的差异,讨论了随着摩擦时间增加,薄膜上磨痕及Al_(2)O_(3)对偶球上转移膜的结构变化对摩擦行为的影响.试验结果显示:a-C:H薄膜在干燥氮气中摩擦具有比在空气中更低的摩擦系数和更长的磨损寿命.微观结构分析表明,转移膜可以起到降低摩擦的作用,在干燥氮气中,随着摩擦进行,Al_(2)O_(3)对偶球上逐渐形成具有典型DLC特征的碳转移膜并稳定地存在,这是摩擦性能进一步提高的原因.此外,在干燥氮气中摩擦,磨痕表面和对偶球上转移膜表面结构均趋于"石墨化".上述二者的共同作用使得a-C:H薄膜在N_(2)环境下比在空气中更低的摩擦磨损.

In this study,a-C:H film was prepared by midfrequency reactive magnetron sputtering system,and a ball-ondisk reciprocating tribometer was used to investigate the friction behaviors of a-C:H film in air and dry nitrogen(N2)atmospheres. The influence of structural changes of wear tracks and transfer films on Al2 O3 counterpart balls between sliding interfaces on friction behaviors were discussed. The results showed that the a-C:H film had lower friction coefficient and longer wear life in nitrogen than in air. The microstructure analysis showed that the transfer film reduces friction. In dry nitrogen,a stable carbon transfer film with typical DLC characteristic formed on Al2 O3 counterpart balls,which further improved the friction performance. In addition,in dry nitrogen,the structure of the wear track and the transfer film tended to be "graphitized". Therefore,it is the combined action of the above two that resulted in lower friction and wear of a-C:H film in N2 atmosphere than in air.