氮化钛硬质薄膜在不同种类润滑油下的摩擦学性能研究

采用球-盘摩擦试验机分别考察了氮化钛硬质薄膜与轴承钢和氮化硅陶瓷组成的摩擦副在不同种类润滑油条件下的摩擦学性能,并表征了其磨痕表面形貌与元素成份.结果显示:与Ti N硬质薄膜干摩擦性能相比,润滑油可显著降低摩擦系数,延长磨损寿命,且具有较长烷基碳链的润滑油性能较优;当上试球材料不同时,其油润滑条件下的性能亦不同.相同润滑油条件下,氮化硅球作为摩擦副时,其润滑性能优于轴承钢球.磨痕表面形貌及能谱分析结果表明:具有较长烷基碳链的润滑油在摩擦副研磨滑动过程中起到油性剂的作用,而短碳链硅油分子结构中含有氯元素,虽通过摩擦化学反应生成边界润滑膜,但不完整致密,以致短时间内润滑失效.

Tribological Properties of TiN Hard Film Lubricated With Different Liquid Lubricants

Liquid lubricants can improve the tribological properties of hard films. The tribological performance of titanium nitride (TiN) hard film against bearing steel and silicon nitride respectively was evaluated using a ball-on-disk tribo-tester under lubrication of several kinds of lubricating oils. The morphologies and element contents of wear tracks were characterized by scanning electron microscopy and energy dispersive spectrometer. The results show that the lubricating oils reduced the friction coefficient, and enhanced the test duration markedly. And lubricating oils with longer alkyl carbon chains exhibited better lubricating properties than that with shorter chains. Moreover, the materials of upper balls had distinct influence on the lubricating performance. Better lubricating property was obtained using a silicon nitride ball in comparison with a bearing steel ball. The analysis results show that wear tracks were smoother under lubrication of lubricating oils with long carbon chains than silicone oil with short alkyl carbon chain. However, the latter silicone oil contains element chlorine, which was one of the key ingredients of extreme pressure additives. Wear and friction coefficient of TiN hard film lubricated with short alkyl carbon chain silicone oil were higher than that lubricated by the rest lubricating oils. The boundary lubricating film, which was formed by tribochemical reaction between element chlorine and elements of the substrate was not compact and continuous, was poor in wear resistance.