EFFECT OF BINDER COMPOSITION AND SINTERING TEMPERATURE ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF WC-7(Ni,Fe) HARD ALLOYS

Abstract

In this research, WC-7(Ni,Fe) hard alloys were prepared by ball milling, cold compaction and finally consolidated by hot isostatic pressing. The effect of binder composition and sintering temperature were investigated in term of the microstructure, density and mechanical properties of sintered samples. Density of hard alloys was measured by the Archimedes' principle while the microstructure was observed using a scanning electron microscope. The Vickers hardness was investigated at load of 30KG and the fracture toughness was calculated based on the Palmqvist crack method. The results revealed that the density of sintered samples was obtained in the range of 14.65 to 14.8 g/cm3 meanwhile the measured Vicker hardness and fracture toughness were respectively achieved from 1260 to 1520 HV30 and 11,7 to 17,5 MPa.m1/2 depending on the binder composition and sintered temperature.

Keywords

• hard alloys
• hot isostatic pressing
• Vickers hardness
• fracture toughness