(中南大学 粉末冶金国家重点实验室，长沙 410083)
摘 要: 采用粉末冶金热压的方法制备Ag-MoS2复合材料，研究银合金粉末的粒度对复合材料的组织结构、力学性能和摩擦磨损性能的影响。结果表明：随着银合金粉末粒度的减小，MoS2团聚体在基体中的分散性得到改善，材料的硬度和抗弯强度同时也得到大幅提高。银合金粉末较小时，复合材料的稳定摩擦因数较低且较平稳；当粉末粒径大于38 μm时，复合材料的磨损量显著增大。MoS2团聚体弥散的涂覆在磨损表面上形成了不连续的润滑膜，提高MoS2在基体的分散性有利于增加润滑膜在磨损表面的覆盖面积，从而减轻表层材料的剪切应力和减少金属与金属之间的接触，降低材料的摩擦与磨损。
关键字: Ag-MoS2复合材料；粉末粒度；自润滑；摩擦；磨损
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:The Ag-MoS2 composites were prepared by powder metallurgy method. The effects of the atomized Ag-Cu alloy particle size on the microstructure, mechanical properties and tribological performances of composites were investigated. The results show that the dispersion of MoS2 particle in matrix and the mechanical properties of composites are dramatically improved by reducing the particle size of alloy powder. The composite has a low and stable friction coefficient when the small size alloy particle is used. When the particle size of alloy powder is above 38 μm, the wear loss of the composite increases severely. SEM observation indicates that the worn surface is covered with smeared MoS2 particles and discontinuous lubricating film is formed on it. The area of lubricating film covered on the worn surface increases with increasing the homogeneity of MoS2 in the matrix, and a large area of lubricating film can reduce the magnitude of shear stress transferred to subsurface and prevent the metal-to-metal contact. Therefore, it helps to reduce the friction and wear of composite.
Key words: Ag-MoS2 composite; particle size; self-lubricating; friction; wear
