"Hard metal - cubic boron nitride (cBN)" composite materials are rarely used in industrial applications. Although its physical properties are similar to diamond, cBN has the inconvenience of reacting with hard metal during the sintering process. A way to eliminate this negative effect is to apply high pressures (up to 9,0 GPa) during the sintering process. In the experiments, hard metal (WC+15%Co) and cBN (16% of the volume) powder mixtures had been submitted to high pressures about 6,0 and 7,0 GPa, and temperatures from 1200 to 1400º C, for 40 seconds. After the sintering processes, the sample that showed the best result had density of 14,81 g/cm3, Knoop hardness of 20,8 GPa, compression limit of 5,2 GPa, and a wear of 0,21 g per each 5 min of use.
Hard metal; cubic boron nitride; high pressure; sintering
