Production of WCu electrical contact material via conventional powder metallurgy method: Characterization, mechanical and electrical properties

    In this study, the effects of increase of sintering temperature and Cu amount on microstructure, mechanical and electrical properties of WCu electrical contact materials fabricated via conventional powder metallurgy (P/M) method were investigated. The powders obtained by adding copper at different ratios into the tungsten powders were cold pressed in a mold under 60 MPa pressure. Samples were sintered at 1000 oC and 1100 oC using three different compositions (W-%10wtCu, W-%20wtCu- and W-%30wtCu). Microstructures of the samples were investigated by scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX) and x-ray diffraction (XRD) analysis. Mechanical properties were determined by measuring hardness values and electrical properties were determined by measuring electrical resistivity. When the effect of the copper ratio on the microstructure, mechanical and electrical properties is analyzed, the reduction in the amount of copper has a positive effect on the hardness, while the electrical conductivity is adversely affected. In addition, the application of the sintering temperature above the melting temperature of copper has been effective in increasing the hardness and electrical conductivity values.

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