材料期刊网

钛合金的耐磨度较差,因其严重的粘着磨损倾向,不适合润滑滑动.通过织构化和表面涂层进行表面修饰,以提高钛合金基体的表面性能.硬质和耐磨涂层如TiAlN和AlCrN被应用于钛合金表面,以铬作为中间层.为了进一步提高硬质涂层的耐摩擦磨损性能,使用固体润滑剂二硫化钼沉积在硬质涂层的的微坑.采用销-盘实验对涂覆基材进行单向滑动磨损测试,以评估其摩擦性能.在3个不同的载荷、时间40 min、2 m/s滑移速度下进行测试,分析研究多层涂层的摩擦行为,如涂层结构、摩擦因数和比磨损率.在滑移初期阶段,摩擦因数较低,约为0.1,这降低了材料转移,延长了耐磨寿命.除去部分二硫化钼涂层后,摩擦因数增大到较高值,硬质复合层仍然保护基体以免磨损.

Titanium alloys are poor in wear resistance and it is not suitable under sliding conditions even with lubrication because of its severe adhesive wear tendency. The surface modifications through texturing and surface coating were used to enhance the surface properties of the titanium alloy substrate. Hard and wear resistant coatings such as TiAlN and AlCrN were applied over textured titanium alloy surfaces with chromium as interlayer. To improve the friction and wear resisting performance of hard coatings further, solid lubricant, molybdenum disulphide (MoS2), was deposited on dimples made over hard coatings. Unidirectional sliding wear tests were performed with pin on disc contact geometry, to evaluate the tribological performance of coated substrates. The tests were performed under three different normal loads for a period of 40 min at sliding velocity of 2 m/s. The tribological behaviours of multi-layer coatings such as coating structure, friction coefficient and specific wear rate were investigated and analyzed. The lower friction coefficient of approximately 0.1 was found at the early sliding stage, which reduces the material transfer and increases the wear life. Although, the friction coefficient increased to high values after MoS2 coating was partially removed, substrate was still protected against wear by underlying hard composite layer.