基于LFM的类金刚石膜纳米摩擦现象研究

Study of nanotribology of ultrathin diamond-like carbon (DLC) based on lateral force microscope (LFM)

使用原子力显微镜(AFM)中的侧向力(LFM)模式对类金刚石膜纳米尺度的摩擦现象进行了研究,主要考察了载荷、微观形貌、粘附对类金刚石膜纳米摩擦性能的影响。首先结合粘附的影响提出了适用于外加载荷在100nN以下类金刚石膜纳米摩擦力表征的修正Amonton公式。其次,试验发现摩擦过程中表面接触峰的斜率对薄膜的微观摩擦力的影响较大,微观摩擦系数与倾角θ成正比例关系,最后结合两者给出了综合考虑载荷、表面形貌、粘附且可用于类金刚石膜纳米尺度摩擦力表征的数学方法。

Nanotribology of untra-thin diamond-like carbon(DLC) coatings deposited by electron cyclotron resonance microwave plasma chemical vapor deposition(MP ECR-CVD) were analyzed by nanoscale friction tests using a lateral force microscope (LFM). These tests are concerned in effect of the stiction, applied load and micro-topography during the friction. The results show that friction force is direct proportional to applied load, although a stiction caused deflection exits, which can be described by a revised Amonton formula. Topography also plays an important role in nanoscale tribology of DLC coatings and the increase of contact peak inclination makes the micro friction coefficient higher. A formula concerning applied force, stiction and topography effects is given to describe the nanotribology of DLC coatings.