Metal-diamond materials obtained by electric resistance sintering: microstructure, processing and mechanical properties

Metal-diamond tools are well established in the mining sector for the cutting of granite, marble and others. To date, the manufacturing process of diamond tools consists of at least two main steps (cold pressing and sintering by hot pressing or furnace sintering). This process takes several hours. This work presents the fabrication of metal-diamond tools by a very fast process, Electric Resistance Sintering. This method permits the pressing and densification of the pieces in few seconds and without protective atmosphere. This work presents the effect of the processing parameters on the microstructure and mechanical properties of the materials. The characterization of the products includes the microstructural analysis and hardness. It was possible to obtain good densification of the compacts and mechanical properties showed interesting results. Two different compositions were used. One of them was based in cobalt-diamond, a very well-known material for metal-diamond tools. In addition, another composition based in Fe-Cu-Ni was also tested.