钛硅碳衍生碳涂层在真空中的摩擦与磨损行为研究

Friction and Wear of Ti_3SiC_2-derived Carbon Coatings in Vacuum

采用高温氯化法(800℃,5%Cl2+Ar)制备了钛硅碳衍生碳涂层(CDC@Ti_3SiC_2).通过真空浸渍处理,将1-己基-3-甲基咪唑六氟磷酸盐离子液体(LP106)浸渍到多孔层状结构的CDC@Ti_3SiC_2涂层中,得到固-液复合润滑涂层(CDC@Ti_3SiC_2-LP106).以Si_3N_4球为摩擦配副,分别考察了Ti_3SiC_2、CDC@Ti_3SiC_2和CDC@Ti_3SiC_2-LP106涂层在两种真空模式下的摩擦磨损性能.这两种真空模式分别为固定真空度(10–4Pa)和改变真空度(由105Pa逐渐减小至10–4Pa).随着真空度的增大,CDC@Ti_3SiC_2涂层的摩擦系数呈现先减小后增大的趋势.相比较而言,CDC@Ti_3SiC_2-LP106涂层的摩擦系数低且对真空度变化不敏感.在两种真空模式下,CDC@Ti_3SiC_2和CDC@Ti_3SiC_2-LP106涂层均显著减小了Ti_3SiC_2的摩擦系数,但其抗磨损性能并没有明显提高.

Carbide derived carbon coating on Ti3SiC2 substrate （CDC@Ti3SiC2） was prepared by chlorination at 800 ℃ in a flow of 5% Cl2 ＋ Ar gas mixtures. By using the porous and lamellar structure of the CDC@Ti3SiC2 coating as a reservoir for ionic liquids （e.g. 1-hexyl-3-methylimidazolium hexafluorophosphate, LP106）, a solid-liquid duplex lubricating coating（CDC@Ti3SiC2-LP 106 coating） was obtained by vacuum impregnation.The tribological properties of bare Ti3SiC2, CDC@Ti3SiC2 coating and CDC@Ti3SiC2-LP106 coating sliding against a Si3N4 ball were investigated in two modes, i.e. high vacuum （10-4 Pa） and progressive evacuation from 105 to 10-4 Pa. The friction coefficient of CDC@Ti3SiC2 coating firstly decreased with the decreasing background pressure and then increased in high vacuum. In comparison, the friction coefficient of CDC@Ti3SiC2-LP 106 coating was low and insensitive to the variation of the background pressure. In both modes, CDC@Ti3SiC2 coating and CDC@Ti3SiC2-LP106 coating significantly reducedthe friction coefficient of bare Ti3SiC2 without obvious improvement on the wear resistance.