类陨石坑表面类金刚石薄膜的制备及摩擦特性

为了提高DLC（Diamond-like Carbon）类金刚石薄膜与SAE1060碳素钢基材的结合强度，以延长发动机活塞环的使用寿命，研制了一种带有复合阳极的RF-DCCVD双电源化学气相沉积设备。利用锯齿结构的辅助阳极产生尖端放电，制备了具有微米类陨石坑非连续结构的DLC薄膜，并利用Ball-on-Disk摩擦评价试验机评价了薄膜的摩擦特性。着重研究了极间距S -T对薄膜表面类陨石坑密度的影响；最后利用拉曼光谱仪分析了薄膜结构和成分。结果表明：在同样的电压下，类陨石坑的密度随着电极间距的增加而减小，最佳电极间距S -T为40~60 mm，此时不仅具有比较适中的类陨石坑密度，对DLC薄膜的摩擦特性影响不大，而且具有较强的界面结合强度。当S-T为50 mm，施加载荷为3 N时，薄膜的破坏寿命达到了130万循环，比光滑表面的薄膜延长了30万循环。得到的结果显示微米类陨石坑非连续结构能够有效地释放膜内的残余压缩应力，延长SAE1060碳素钢基材上沉积类金刚石薄膜的使用寿命。

Deposition and friction properties of DLC films with micro-crater-like structures

To enhance the adhesive strength between a Diamond-like Carbon(DLC) film and a SAE1060 substrate and to prolong the service life of engine piston rings, the RF-DCCVD dual power chemical vapor deposition equipment with a composite anode was developed. The auxiliary anode with zigzag was used to produce cutting-edge discharge, and the DLC films with micro-crater-like structures were formed. Then, the friction properties of the films were experimentally evaluated with a "Ball-on-Disk" wear testing machine. The effects of electrode spacing S-T on the density of the micro-crater-like on the surface of the films were studied and the structure and composition were determined by a Raman spectrometer. The experimental results indicate that the micro-crater-like density on the surface of DLC films decreases with the increase of the electrode spacing (S-T) under the same voltage. The best electrode spacing is 40-60 mm, in which there is a relatively moderate micro-crater-like density, a relatively strong adhesive strength at the interface and little effect on the friction characteristics. When S-T is 50 mm or so, there is a maximum in the failure lifetime, which reaches approximately 1.3 million cycles as applying the load of 3 N,and 300,000 cycles are increased over films with a smooth surface. In conclusion, the micro-crater-like discontinuous structures effectively reduce the residual compressive stress within films, and the failure life of DLC films deposited on SAE1060 substrates is effectively prolonged.