Production and Properties of Carbide Dispersion-strengthened Coppers by Compocasting

Abstract

An investigation was made on the electrical and mechanical properties of dispersion-strengthened (DS) coppers compocast at 25 rev/sec with the addition of fine carbide particles in the range of 0.5 to 30 mass% WC, TaC, VC, TiC, NbC, ZrC, Mo₂C, Cr₃C₂ and Al₄C₃. Homogeneous dispersion of carbides was observed in the microstructures of the compocast DS coppers except with the addition of Mo₂C, Cr₃C₂ or Al₄C₃. The measured values of electrical conductivity of the DS coppers were 77.9%IACS at 20 mass% WC, 73.4%IACS at 20 mass% TaC, 72.0%IACS at 10 mass% NbC, 85.2%IACS at 5 mass% TiC and 68.9%IACS at 5 mass% VC. The values of Vickers hardness were HV 197 at 30 mass% WC, HV 155 at 30 mass% NbC, HV 110 at 30 mass% TaC, HV 158 at 20 mass% VC and HV 121 at 20 mass% TiC. Ultimate tensile strength values were 402 Mpa at 30 mass% NbC, 357 Mpa at 20 mass% TiC, 330 Mpa at 20 mass% WC, 269 Mpa at 20 mass% TaC and 323 Mpa at 10 mass% VC. The values of elongation were 12.9% at 20 mass% TaC, 10.9% at 20 mass% WC, 25.2% at 10 mass% NbC, 21.8% at 10 mass% VC and 17.5% at 5 mass% TiC.