Study Of Cu Matrix Graphite Friction Composite By Powder Metallurgy

To make Cu/C composite material by powder metallurgic method. The moldpressure, sintering temperature and the re-pressing of powder metallurgic methodhave been investigated. The tribology property and wear mechanism of Cu/Ccomposite material have been systemtically studies by rubbing machine. In addition,the wear mechanism of Cu/C composite material has been exposit.The experimental results indicate that the relative density will be higher whenthe mold pressure go bigger in appropraite pressure intervals,when the mold pressureis380Mpa, the relative density go up slowly because it is almost saturation. The firstsinter make relative density go up so much. When the temperature get1050℃, theexperiment is fail because copper substrate outflow.970℃is the best sintertemperature. The relative density will10%higher on that temperature level. Therelative density of380Mpa mold pressure is2%-3%smaller than the relative densityof320Mpa mold pressure.It is found that the percentage of grapghite affect hardness and pressureresistance so much. The hardness and pressure resistance will go higher if thepercentage of grapghite go lower. The hardness and pressure resistance could gohigher if copper paint on grapghite, the reason is Cu/Copper-coated graphitecomposite material has uniform inner structure. But the Cu/C composite materialwith jumbled inner structure has6%better compressive deformation thanCu/Copper-coated graphite composite material. When the percent of graphite goes15%, the pressure resistance is130Mpa and shape changing is15%. It close toforeign product quality.The friction-wear test show that frictionfactor and wear rate will decrease whenpercentage of graphite increase. The wear rate and frictionfactor goes lower whenraise friction speed or increase loading pressure. The wear rate could go40%higherif copper paint on grapghite, but the frictionfactors are almost same. When the percent of graphite goes15%, the frictionfactors is0.57. It close to foreign productquality. The wear loss is0.35%, it is better than oreign product which is0.62%.