钛合金表面自润滑膜的制备及其摩擦磨损性能研究

发布时间：2018-04-12 11:23

本文选题：TC4钛合金 + 化学复合镀　；参考：《东北大学》2011年硕士论文

【摘要】：钛合金具有比强度高、热强性好、耐腐蚀等优点,已成为航空、航天、火箭、导弹、舰艇及能源化工等国防和民用工业部门的重要结构材料,发展前景十分广阔。其中TC4(Ti-6A1-4V)钛合金用途最为广泛,用量占钛合金总量的一半以上。但钛合金硬度低,耐磨性能较差,这限制了其在实际中的应用。为了克服钛合金摩擦磨损性能的不足,钛合金表面改性技术已成为该领域内一个新的研究热点。本文分别通过Ni-P-PTFE化学复合镀方法、微弧氧化-复合PTFE涂膜方法在TC4钛合金的表面成功的制备出具有耐磨减摩性能的自润滑膜。同时分别对这两种方法进行了系统地研究和探讨。利用XRD、SEM、EDS等手段对自润滑膜的微观形貌及相成分进行了分析,并采用摩擦磨损试验机测试了其摩擦磨损性能。研究了Ni-P-PTFE化学复合镀工艺,得至PTFE乳液浓度、表面活性剂浓度、施镀温度、pH值等参数对复合镀层中PTFE含量的影响规律；镀层中PTFE的含量是影响复合镀层摩擦磨损性能的关键因素。实验结果表明：化学镀Ni-P镀层和化学复合镀Ni-P-PTFE镀层都可以有效地改善钛合金的摩擦磨损性能,Ni-P-PTFE复合镀层的效果更为明显。当复合镀层中PTFE体积百分含量约为20.39v%时,其摩擦系数降至小于0.2,耐磨性能良好；随着镀层中PTFE含量继续增加,其摩擦系数会继续下降,当PTFE体积百分含量约为26.4v%时,其摩擦系数降至约0.13,但此时镀层结合力差,导致其耐磨性能降低。研究微弧氧化-复合PTFE涂膜处理工艺,讨论分析了微弧氧化电压、氧化时间对多孔膜形貌及相成分的影响,以及微弧氧化-复合PTFE涂膜的摩擦磨损性能。研究结果表明,钛合金微弧氧化-复合PTFE涂膜后,PTFE粒子较均匀占据Ti02孔径内,复合膜的摩擦系数约为0.12,同时具有良好的耐磨性能。
[Abstract]:Titanium alloy has become an important structural material of national defense and civil industry such as aviation, aerospace, rocket, missile, ship and energy and chemical industry, with high specific strength, good thermal strength, corrosion resistance and so on.Among them, TC _ 4 Ti _ 6A _ (1-4) Ti alloy is the most widely used, accounting for more than half of the total amount of titanium alloy.However, titanium alloy has low hardness and poor wear resistance, which limits its application in practice.In order to overcome the deficiency of friction and wear performance of titanium alloy, surface modification technology of titanium alloy has become a new research hotspot in this field.In this paper, self-lubricating films with wear-resistant and friction-reducing properties were successfully prepared on the surface of TC4 titanium alloy by Ni-P-PTFE electroless composite plating and micro-arc oxidation-composite PTFE coating method.At the same time, the two methods are systematically studied and discussed.The micro-morphology and phase composition of the self-lubricating film were analyzed by means of XRDX SEMZEDS and the friction and wear properties of the film were tested by friction and wear tester.The effects of PTFE emulsion concentration, surfactant concentration, plating temperature and pH value on the content of PTFE in the composite coating were studied.The content of PTFE in the coating is a key factor affecting the friction and wear properties of the composite coating.The experimental results show that both electroless Ni-P coating and electroless composite Ni-P-PTFE coating can effectively improve the friction and wear properties of titanium alloy and the effect of Ni-P-PTFE composite coating is more obvious than that of Ni-P-PTFE composite coating.When the content of PTFE in the composite coating is about 20.39 v%, the friction coefficient of the composite coating decreases to less than 0.2, and the friction coefficient will continue to decrease with the increase of the content of PTFE in the coating, and when the volume percentage of PTFE is about 26.4v%, the friction coefficient of the composite coating will continue to decrease with the increase of the content of PTFE in the coating.The friction coefficient was reduced to about 0.13, but the adhesion of the coating was poor, which resulted in the decrease of wear resistance.The treatment process of micro-arc oxidation-composite PTFE film was studied. The effects of micro-arc oxidation voltage and oxidation time on the morphology and phase composition of porous film and the friction and wear properties of micro-arc oxidation-composite PTFE film were discussed.The results show that the particles of titanium alloy after micro-arc oxidation and composite PTFE coating occupy the pore diameter of Ti02 more evenly, and the friction coefficient of the composite film is about 0.12, and the composite film has good wear resistance at the same time.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH117;TG174.4

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