Studies On Microstructure And Properties Of MoS₂-Cu Coated Graphite-Ag Matrix Composites

MoS2-CU coated graphite-Ag matrix composites(group A) and MoS2-graphite-Ag matrix composites(group B) were prepared by powder metallurgy in this thesis;the effect of MoS2content and Cu coated graphite on microstructure and properties of MoS2-Cu coated graphite-Ag matrix composites were studied;the tribological properties with and without electric current of both group A and group B composites were tested using the costom tribometer;tribological properties under different electric current density of2%MoS2-Cu coated graphite-Ag matrix composite was tested at last.Microstructure and worn surface were observed by metallurgy scope and SEM.The results show that for group A composites,density, hardness and bending strength are improved and electric resistivity does not show considerable change with MoS2increasing; Properties of group A composites mentioned above are superior to group B composites.With and without electric current, wear rate of group A composites are much lower than group B composites, while coefficient of friction are slightly higher than group B composites.With MoS2increasing, coefficient of friction of MoS2-Cu coated graphite-Ag matrix composites increase slightly while wear rate decreases remarkably with and without electric current; coefficient of friction under electric current of both group A and group B composites are smaller than those without electric current.2%MoS2-Cu coated graphite-Ag matrix composite has good lubrication and low wear rate when the current density is below20A/cm2.But current density above20A/cm2obviously weaken its friction and wear property.