| The copper-lead (Cu-Pb) alloy powder density was measured by the method of still water weighing. Using XRD, SEM and EDS technique, the phases, component and morphology of Cu-Pb alloy powder were determined. The bimetallic tube sample of steel/Cu-Pb alloy was prepared by the liquid-phase sintering. The sintering mechanism of steel/Cu-Pb bimetal was discussed, and the interface microstructure of steel/Cu-Pb processed at different parameters was examined. By measuring the Cu-Pb alloy powder's green density, sintered porosity, sintered density and the mechanical properties (sintered Cu-Pb alloy hardness, interface shear strength of steel/Cu-Pb alloy), it was studied that the effects of sintered processing parameters on the sintered microstructure and mechanical properties.The results indicate that the density of Cu-Pb alloy powder is 8.7936 g/cm3; Cu-Pb alloy powder belongs to lead coated powder, and its shape is irregular. Steel/Cu-Pb bimetallic sintering mechanism is that, the sintering of Cu-Pb alloy powder's surface agrees with "Liquid-stream" theory put up by Cannon and Lenel, and the sintering inside powder agrees with "Solution-deposition" theory given by Price. While with the sintering time increasing, the lead microstructure evolutes from reticular to spotted and massive and with the compacting pressure increase, the lead microstructure evolutes from spotted and massive to reticular. In the same compacting pressure, the porosity of Cu-Pb alloy powder sintered for 60 min lowers15.7%, 19.3%, 16.7%, 23.7%, 40.2%, and 39.5% than that sintered for 30 min. When sintering at 700℃and 500MPa for 60 min, the biggest density of Cu-Pb alloy of 8.0215 g/cm3 reaches, and relative density is above 90 %; the average hardness of sintered Cu-Pb alloy is the lowest (23.8 HV10) at 300MPa, and the highest (36.6 HV10) at 500MPa. The shear strengths of sintered samples formed by tube expanding are 20～45MPa, and those of samples by mould pressing 55～105MPa.
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