Creation and Tribology of Extremely Low Friction Super Lattice Solid Lubricant Films

1. 纳米期多层固体润滑膜的研制：为了研制具有更低摩擦和更长的寿命的固体润滑膜，研究了纳米期多层固体润滑膜硬度提高的机理，并提出了新型固体润滑膜的模型。为了降低摩擦系数，提高硬度，在使用低剪切阻力材料制备纳米期多层膜后，我们合成的新型纳米期固体润滑膜具有极低的摩擦，而通常的简单膜和混合膜材料则没有如此优越的摩擦性能。具体规定如下：(1)纳米周期碳硼固体多层膜：制备了周期数纳米的（C/BN）n多层膜，其耐热性得到了预期的提高。结果表明，4nm周期多层膜的摩擦系数最低。在200℃的高温下，与其他多层膜相比，该多层膜具有更大的磨损量和更好的耐磨性。(2)电有利安、银纳米期多层固体润滑膜：电有利安、银纳米期多层固体润滑膜采用Au、Ag分层沉积，具有极低的摩擦系数和优异的耐磨性，即4纳米期多层膜的摩擦系数较低，为μ= 0.05，耐磨性显著提高。另一方面，经过滑动测试，纳米周期多层膜的电阻率变化小于单层膜。也就是说，有可能制备出电阻率稳定的优良固体润滑膜。(3)纳米二硫化钨和二硫化钼多层膜：我们所合成的MoS_2和WS_2等纳米多层膜，即使在58%的湿度条件下，其摩擦系数也低至μ= 0.04。在重复磨损试验中，其磨损耐久性比简单薄膜长6倍以上。(4)纳米级加工的实现：由于多层膜上的层的延展性缺陷，使得在每一层上进行纳米级加工成为可能。纳米复合薄膜：在三维纳米复合材料的基础研究中，沉积了含金属类金刚石（DLC）薄膜，并通过纳米压痕和微磨损试验对其摩擦学性能进行了评价。含Ti DLC薄膜表现出优异的微观力学性能。金属的加入改善了合金的边界润滑性能。特别是含Ti DLC膜的摩擦系数较低，小于0.04。该膜的优异摩擦学性能具有巨大的潜力，可以实现在汽车滑动件上的高性能润滑剂和耐用膜的应用，并有望在超低摩擦环境下良好地工作。少

1. Development of nano-period multilayer solid lubricant films: To develop the solid lubricant films with a much lower friction and a longer life, the mechanism of improving the hardness of nano-period multilayer films was investigated and the model of novel solid lubricant films was proposed. In order to reduce a friction coefficient and increase a hardness, after the preparation of nano-period multilayer films using materials with low shear resistances, new nano-period solid lubricant films synthesized in our works exhibit extremely low frictions, whereas usual simple film and mixed film materials do not have such superior friction properties. Concretely, those are specified as follows.(1) Nano-period carbon and boron solid multilayer films: (C/BN)n multilayer films with periods of several nanometers were prepared and their heat resistances were expectedly improved. It has been confirmed that the 4-nm-period multilayer film exhibits the lowest friction coefficient., the neglectable d … More estruction and the superior wear resistances investigated in the wear test at a high temperature of 200^oC as compared with other multilayer films. (2) Electro-conducive An and Ag nano-period multilayer films: Since electro-conducive nano-period multilayer solid lubricant films were deposited using Au and Ag by layers, they are provided with a extremely low friction coefficient and superior wear durability, i.e. the 4-nm-period multilayer film indicates a low friction coefficient as μ= 0.05 and its wear durability was significantly improved. On the other hand, the changes of the electrical resistivity of the nano-period multilayer films are less than those of simple layer films after the sliding test. That is to say, it is possible to prepare superior solid lubricant films with steady electrical resistivity. (3) Nano-period tungsten disulfide and molyddenum disulfied multlilayer films: For those of nano-period multilayer films such as MoS_2 and WS_2 synthesized in our studies, their friction coefficient is as low as μ= 0.04 even under a condition of 58% humidity. Moreover, their wear durability evaluated in the repetitive wear tests is over 6 times longer than that of simple films. (4) Realization of nano-scale processing: As a result of deterring from the defect ductlility of layers on multilayer films, it becomes possible to carry out nano-scale processing in each layer.2. Nano-composite thin films: In the basic researches of the three dimensional nanocomposite, metal containing DLC (diamond like carbon) films were deposited and their tribological properties were evaluated in the nanoindentation and microwear tests. The Ti containing DLC film shows superior micromechanical properties. The boundary lubrication properties were improved by the metal addition. In particularly, the Ti containing DLC film shows the low friction coefficient less than 0.04. The superior tribological property of the film has significant potential and it is possible to realize the application of the superior lubricant and durable films in automobile sliding parts which can be expected to work well under a super low friction environment. Less