Quantitative evaluation of normal and abnormal grain growth of cemented carbides during liquid phase sintering

The liquid-phase sintering (LPS) of cemented carbides prepared from submicronic powders induces a micro-structural evolution generally ascribed to normal and abnormal grain growth. Such phenomena can be prevented by small additions of inhibitors (Cr, V). Presently, the mechanisms controlling either the grain growth or its inhibition are not strictly identified. In the present work, the effects of major parameters on grain growth (initial WC grain size, liquid composition, liquid fraction) are studied by image analysis of specimens sintered at 1450°C up to 8h.The evolution of the mean intercept and intercept distribution of WC grains is analysed in terms of the possible mechanisms involved.