粘结剂成分对WC－20（Fe／Co／Ni）硬质合金力学性能和显微组织的影响

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

用常规的粉末冶金工艺试制了四种成分的ＷＣ－２０（Ｆｅ／Ｃｏ／Ｎｉ）合金，优选粘结剂的成分及总碳量可使其力学性能最佳。着重研究了ＷＣ－２０（Ｆｅ／Ｃｏ／Ｎｉ）合金的力学性能和显微组织，发现：粘结相为李晶马氏体和奥氏体时，其主要力学性能不低于ＷＣ－２Ｃｏ；而粘结相全部为板条马氏体时。

WC-20 (Fe/Co/Ni) cemented carbides were prepared by conventional powder metallurgytechnology. 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 isfound that WC-20 (Fe/Co/Ni ) cemented carbides whose binder phase structure is austenitic andmartensite 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 binderphase structure is lath martensite are inferior to the WC-20Co. The replacement of the cobalt binder inNC cemented carbides through optimum Fe-Co-Ni alloys is attractive not only from the economiCalpoint of view,but also due to the superior properties of the WC-Fe/Co/Ni cemented carbides.