Diamond micro-powders of 28/20 μm mean particle size were sintered under conditions of high pressure of 6.0 and 8.0 GPa at temperatures of 1600, 1700, and 1800 °C during various sintering times, aiming to obtain polycrystalline compacts with required strength. The experiments were carried out by using an anvil type high pressure device with toroidal concavity of 13.5 mm diameter. It was obtained samples with 4.5 mm diameter and 5.0 mm height. It was plotted the polycrystalline diamonds density dependency as a function of the process duration under the above mentioned sintering conditions. The kinetics of powder consolidation was studied by X-ray diffraction, which allowed the establishment of the correlation between the (3 3 1) plane enlargement of diamond and the structural transformations that took place during sintering. Another objective was the study of the graphitization kinetics of diamonds under the action of the sintering parameters. It was concluded that over the established consolidation mechanisms, also acts the partial shear mechanism.
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