Abstract
Composites (for tool blank application) of WC-Co support, tantalum intermediate layer, as a barrier, and sintered diamond were prepared by a simultaneous sintering technique under a high pressure-temperature condition. Tantalum carbide specimens were also prepared from a starting material of TaC powder by treating under identical conditions. The observed microstructures and chemical compositions of the composites are discussed in comparison with that of the specimens. Regarding the principal formation process of the tantalum carbide region observed in the tantalum layer of the composites, it may be suggested that tantalum reacts with cobalt melt to yield an alloy of Ta and Co, which subsequently is converted to tantalum carbide and cobalt.
