THE INFLUENCE OF THE BINDER COMPOSITION ON THE MICROSTRUCTURES AND MECHANICAL PROPERTIES OF WC-20(Fe/Co/Ni) CEMENTED CARBIDES

WC-20 (Fe/Co/Ni) cemented carbides were prepared by conventional powder metallurgy technology. Optimization of the cemented Carbides can be achieved through changes in the binder composition and the total carbon content. The microstructures and mechanical properties were studied. It is found that WC-20 (Fe/Co/Ni) cemented carbides whose binder phase structure is austenitic and martensite plate are equivalent if not superior to the WC-20Co as regards tranverse rupture strength,hardness, hot hardness and fracture toughness. The properties of WC-20 (Fe/Co/Ni) whose binder phase structure is lath martensite are inferior to the WC-20Co. The replacement of the cobalt binder in WC cemented carbides through optimum Fe-Co-Ni alloys is attractive not only from the economical point of view,but also due to the superior properties of the WC-Fe/Co/Ni cemented carbides.