Study On Mechanical Performance And Wear Performance Of P/M Copper Infiltrated Iron

Through the process of pressing, sintering and copper-infiltrating, a kind of hydraulic copper-infiltrated sintering iron was obtained. Study of the microstructure and the law of the mechanical performance changing was carried out. Materials’wear performances changing with different copper infiltrating amount and various matrix densities were also studied. And wear performances of formerly used wear-resistant alloys were also tested to give a comparison.It showed that:microstructure was composed by lamellar pearlite and ferrite before copper-infiltrating and changed to spheroidal pearlite, ferrite and copper. Mechanical performance was greatly improved by the copper-infiltrating process. Tensile strength of the material, which density is6.4g/cm3, is only230MPa. After the copper-infiltrating treatment, the tensile strength can reach595MPa. Strengths of the same density substrates increased with the growing amount of the copper infiltrating. With the same amount of infiltrated-copper, strengths improved with higher matrix density.The UMT-3Tribometer was used to evaluate the friction and wear performance under boundary lubrication conditions. It showed that: materials of different matrix densities infiltrated with the same amount of copper had almost the same friction coefficients; friction coefficients of the same density substrates increased first and then stabilized with the growing amount of copper infiltration. Wear loss first reduced and then increased. When the matrix density is6.6g/cm3, copper-infiltrated amount14%, it has the best wear property. Performances of formerly used wear-resistant alloys were also studied to give a comparison. Results showed that:coefficients of the P/M copper infiltrated iron friction pair is a little higher, but the wear loss is much smaller. Friction surfaces of the two groups are both smooth, which result in a good working state.