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

Year 2017, Volume: 6 Issue: 1, 37 - 42, 05.10.2017

Ali Erçetin , Kubilay Aslantaş

Abstract

    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.

Keywords

Powder metallurgy, tungsten-copper, microstructure, hardness

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