1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China; 2. CRRC Qishuyan Institute Co., Ltd., Changzhou 213011, China
Abstract：Resin-coated graphite/copper composites were prepared by powder metallurgy pressure sintering process using resin-coated graphite and electrolytic copper powders as raw materials, the density, porosity, conductivity, hardness, bending strength, shear strength, and friction property of the composites were measured, the effects of resin-coated graphite content on the microstructure and properties of copper matrix composites were studied by scanning electron microscope. The results show that the continuity of copper matrix gradually decreases, and the distribution of graphite is gradually changed from discrete to aggregate with the increase of resin-coated graphite content. The high content of graphite hinders the sintering densification of copper particles, and as a “defect”, graphite inhibits the sintering continuity of copper matrix, meanwhile the density, conductivity, hardness, bending strength, and shear strength of the composites are decreased. As a lubricating phase, the graphite can effectively improve the friction and wear property. When the addition of resin-coated graphite reaches 16% (mass fraction), the friction coefficient of the composites is the lowest (0.23), the friction coefficient curve is relatively stable, the friction surface is the smoothest, and the friction and wear property is the best.
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2023, Vol. 28 
