POWDER METALLURGY PROCESSING OF HARDMETAL POWDER

Abstract

The microstructure and mechanical properties of sintered 94WC-6Co powders were investigated. In this work, sub-micron (< 1μm) of tungsten carbide (WC), cobalt (Co) and paraffin wax powders were wet mixing in a tubular mixer at a mixing speed of 50 rpm for 3 hours. Powders mixture were uniaxially pressed, cold isostatic pressing (CIPped) and sintered at 1200-1500°C for 1 hour in a nitrogen-based atmosphere using liquid phase sintering (LPS) mechanism. The fine WC particles were led to uniformity in microstructures at optimum sintering temperatures, 1450°C and showed a relative sintered density above 95% of theoretical. The sintered samples also obtained higher hardness and strength due to their fine microstructures, which are suitable for use in cutting tool application.