Diamond-coated substrates

摘要

A composite structure, comprising a cemented carbide substrate (e.g., tungsten carbide substrate cemented with cobalt, such as WC—Co), a thin interlayer disposed over the substrate, and a contiguous diamond film disposed over the interlayer, as well as processes of preparing such a composite structure and uses thereof, are provided. The composite structure is characterized by at least one of a substrate binder concentration of at least 2 percents by weight, interlayer thickness less than 20 microns, a homogenous interlayer made substantially of crystalline chromium nitride, a low to null binder concentration in the interlayer, and a high co-adhesion of the diamond film to the interlayer and the interlayer to the substrate.

主权项

1. A composite structure, comprising a cemented carbide substrate, an interlayer disposed over said substrate and a contiguous diamond film disposed over said interlayer, wherein said cemented carbide substrate comprises a binder, and said interlayer comprises crystalline chromium nitride, the composite structure being characterized by at least one of:
a thickness of said interlayer which is lower than 20 microns; a concentration of said binder in said interlayer which is lower than 0.5 percent by weight; a concentration of amorphous carbon in said interlayer which is lower than 0.5 percent by weight; and a co-adhesion of said diamond film to said interlayer and of said interlayer to said substrate, which is exhibited by a microhardness test at a load of at least 20 kg.