Cast steel rock bit cutter cones having metallurgically bonded cutter inserts

A cutting tool to be used for shaping of materials, the tool comprising:

• at least one hard cermet insert forming a first base end and a second cutting end, said insert comprising a metal carbide in a suitable metal binder phase;
• a first metal layer disposed on the first base end of the cermet insert, said metal layer being selected from a group consisting of copper and copper alloys;
• a second high temperature protective metal layer disposed on top of said first copper metal layer;
• and
• a steel matrix surrounding said first base end of the cermet insert, the matrix having been cast in a molten state into a suitable mold while the base end of the layered cermet insert is held in the mold in operative position while the molten steel encompasses said base of said insert, the metal of the first copper layer forms a barrier to block diffusion of carbon from the insert into the surrounding steel matrix during the casting process, the second high temperature metal layer protects the first copper layer of metal, the surface of the high temperature layer partially melts at the temperature of the molten steel matrix, the steel matrix is thereby metallurgically bonded to the second high temperature layer.