新型铜基自润滑材料的制备

Preparation of a New Cu-Based Self-Lubricating Composite

实验设计以Cu—Ni—sn—Pb雾化合金粉末为基体，添加钨、纳米Al2O3强化相，以二硫化钼和1．5％，2．0％，2．5％，3％，4％不同质量分数石墨作为固体润滑相组成新的复合材料体系，利用粉末冶金技术制备一种新型铜基自润滑材料．应用数码显微镜、x射线衍射和显微硬度仪等分析技术，对实验样品的制备工艺、组织结构和性能进行了研究．结果表明：优化的烧结工艺为温度880～900℃，烧结时间3h；随着石墨增加使得样品的硬度和强度降低；2％石墨铜基自润滑材料的密度为6．41g／cm^3，硬度为38HV，可以初步满足低速运转条件下机械自润滑零件的应用．

With the atomized Cu-Ni-Sn-Pb alloy powder as matrix, and the additives W and nano-Al2O3 as strengthening phase, a new composite system was constituted taking molybdenum disulfide （MoS2） plus graphite of 1.5, 2.0, 2.5, 3.0 and 4wt. % as solid lubricant phase. Then, a new copper-based self-lubricating composite was prepared through powder metallurgy. The preparation process, structure and mechanical properties of its samples were studied by means of digital microstructure microscopy, XRD and micro Vickers. The results showed that： the optimized sintering process should be done at 880- 900 ℃, for 3 hr, and the hardness and strength both decrease with increasing graphite content. Among the samples containing different graphite mass fractions, the copper-based self-lubricating composite containing 2wt. % graphite is regarded as better, of which the density is 6.41 g/cm^3 and hardness 38 HV, and it has been proved basically available to meet the requirement for low-speed self-lubricating machines.