CUTTING TOOL HAVING EXCELLENT IMPACT RESISTANCE MADE OF TUNGSTEN CARBIDE-BASE SINTERED HARD ALLOY

摘要

PURPOSE:To manufacture the title cutting tool having excellent impact resistance at the time of coating the surface of a tungsten carbide-base sintered hard alloy matrix by forming at least one layer of the hard layer with a ceramic whisker reinforcing layer. CONSTITUTION:A hard layer consisting of a single layer constituted of one kind among the carbide, nitride and boride of (Ti, Zr, Hf and Al) or a complex layer constituted of two or more kinds among those is formed on the surface of a WC-base sintered hard alloy matrix contg. preferably about 4 to 15% of one or more kinds among iron metals, contg., at need, about 0.5 to 40% of one or more kinds among (Ti, Ta, Nb, W)C. and the balance WC with inevitable impurities into about 0.5 to 20mu average layer thickness by a chemical deposition method or the like to prepare a cutting tool. At this time, at least one layer of the hard layer is constituted of a ceramic whisker reinforcing layer to provide the tool with excellent impact resistance. By this method, the cutting tool made of the surface coated WC-base sintered hard alloy having no generation of deficiency and chipping in its cutting edge even if used under severe conditions can be obtd.