Diamond micro-powders of 28/20 mm mean particle size were sintered under conditions of high pressure of 6.0 and 7.0 GPa at temperatures from 1600 to 1800 ºC during various sintering times until 80 s, aiming to obtain polycrystalline compacts with required strength. The experiments were carried out by using an anvil type high pressure device with toroidal concavity. 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. 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.
polycrystalline diamond; high pressure; sintering; consolidation mechanisms
