High-Temperature Plasma Sintering of the Mixture of Different Fractions of the Plasmadynamic Synthesis Product

Resumo

The paper examines a technique for producing metal-cutting ceramics from the plasmadynamic synthesis product using the spark plasma sintering technology. It studies the dependence of physico-mechanical properties of ceramics on the mixture parameters. Increase in bulk density and effect produced by this increase are well observed when comparing the sintering process curves. Movable die displacement for non-activated powder is 3.5 mm, while powder activation allowed reaching the 1.75 mm displacement, other conditions being equal. Hardness of produced materials measured by Vickers method was 21 GPa for non-activated powder and 17 GPa for activated powder at relative densities of sintered ceramic workpieces in relation to osbornite monocrystal of 92% and 93.5% respectively. Significant increase in density of the sintered body is ensured mainly by elimination of the raw material agglomeration.