背景:银基复合材料是一种常见的电接触材料,具有良好的导电导热性能;而二硫化钼是一种重要的固体润滑材料,具有良好的减摩润滑性能.因此考虑把二硫化钼添加到银基体材料中,以制备适用于滑动电摩擦磨损过程的复合材料.目的:制备不同含量配比的银-二硫化钳复合材料,通过对其力学性能以及电摩擦磨损性能的比较,得到最佳含量组成的复合材料.设计、时间及地点:观察对比实验,于2008-04/05在合肥工业大学材料科学与工程学院完成.材料:银粉由蚌埠金银饰品厂提供,二硫化钼粉由国药化学试剂有限公司提供.方法:采用粉末冶金方法,经配料、烘干、混料、初压、烧结、复压等过程,制备二硫化钼含量为12.0%,13.5%,15.0%.16.5%,18.0%的银-二硫化钼复合材料.主要观察指标:利用万能力学实验机对材料的抗弯强度进行测试,光学显微镜观察其烧结过后的组织形貌;使用自制的电磨损试验机对试样进行电摩擦磨损实验,并用扫描电子显微镜对试样磨损表面进行观察分析.结果:随着复合材料中二硫化钼含量的增加,材料的抗弯强度下降,电阻率升高,磨损率先降低后升高,在二硫化钼含量为15%时材料的磨损量最低.结论:二硫化钼含量在15%时综合性能指数最佳.%BACKGROUND: Silver-matrix composite is usually used as a kind of electrical conductive matedal, which has excellent properties in electrical and heat conducting. MoS2, which used as a common solid lubricating material, has unique anti-frictional and lubricating properties in the process of wearing. Ag-MoS2 composites using in the area of electrical sliding wear were fabricated by adding MoS2 to the silver-matrix. OBJECTIVE: Ag-MoS2 composites with different content of MoS2 were produced to gain the mixture ratio for best properties by the experiments of mechanical and wear test. DESIGN, TIME AND SETTING: The controlled experiment was performed at the Department of Matedal Science and Engineering, Hefei University of Technology from April to May 2008. MATERIALS: Silver powder (Bengbu Gold and Silver Article Factory, China) and MoS2 powder (Sinopharm Chemical Reagent Co., Ltd., China) were used in this study. METHODS: Ag-MoS2 composites for five different contents were fabricated by powder metallurgy method, which included the processes of powder mixture, drying, initial pressure, sintering, and second pressure. MoS2 contents were the MoS2 composite of 12.0%, 13.5%, 15.0%, 16.5%, 18.0% silver- MoS2. MAIN OUTCOME MEASURES: Flexural strength was measured by versatility mechanical testing machine. The microstructures of the composites after sintering were observed by an optical microscope. The electrical sliding friction and wear properties were tested by the electrical wear test machine. The worn surfaces of the samples were observed by a scanning electron microscope. RESULTS: With the increase in MoS2, the flexural strength decreased, the resistivity increased, and the wear loss decreased first, and then increased, which comes the lowest point when the MoS2 content was 15%. CONCLUSION: When the content of MoS2 is 15%, the average properties was the best.
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