Precipitate-strengthened hard metal-diamond composite

A method of manufacturing a cutting element, the method comprising:

• sintering diamond and tungsten carbide particles in the presence of Co and W to about 1520° C. or greater under pressure of about 57 kbar or greater to form a hard metal-diamond composite compact and solubilize carbon and tungsten within the compact;
• cooling the cutting element at about 1° C./sec or greater to form a cobalt-tungsten metallic phase in the compact;
• and
• subsequent to cooling the cutting element, heat-treating the cutting element to precipitate carbon and tungsten in the compact as an intermetallic phase comprising Co3WCx, where 0<x≤1.

A method of forming a cutting table of a cutting element comprising:

• sintering diamond and tungsten carbide particles in the presence of cobalt and tungsten to about 1520° C. or greater under about 57 kbar to about 70 kbar of pressure to form a hard metal-diamond composite compact and solubilize carbon and tungsten between diamond and tungsten carbide particles of the compact;
• cooling the cutting element at about 5° C./sec or greater to form a cobalt-tungsten metallic phase in the compact;
• and
• subsequent to cooling the cutting element, heat-treating the cutting element to precipitate carbon and tungsten as an intermetallic phase comprising Co3WCx, where 0<x≤1, between diamond and tungsten carbide particles of the compact, wherein the heat-treating is performed at 600 to 800° C. for at least 10 minutes.