SURFACE COVERED CEMENTED CARBIDE MADE END MILL ON WHICH HEAD END SURFACE CUTTING SURFACE AND OUTER PERIPHERAL BLADE DISPLAY EXCELLENT HEAT RESISTANT PLASTIC DEFORMATION PROPERTY

摘要

PROBLEM TO BE SOLVED: To provide a surface covered cemented carbide made cutting end mill on which a heat end surface cutting surface and an outer peripheral blade display an excellent heat resistant plastic deformation property. SOLUTION: A tool base body is constituted of WC group cemented carbide containing Co: 5-20 mass %, Cr: 0.1-1 mass %, Al: 0.01-0.5 mass % in proportion occupied by a Co group alloy of a connecting phase as a whole on which WC occupying 75-95 area % exists as a dispersed phase and the remaining is made of a connecting phase of the Co group alloy and unavoidable impurities in structural observation by a scanning type electronic microscope on the surface covered cemented carbide made end mill constituted of a hard covered layer made of a single layer or a multiple layer of a Ti and Al composite carbide layer, a composite nitride layer and a composite carbonitride layer physically deposited in average thickness of 0.5-6μm on a surface of the tool base body as well as the tool base body of WC group cemented carbide at least on the cutting blade part out of the cutting blade part and the shank part by making the head end surface a cutting blade surface and making it of the cutting part on which the outer peripheral blade is formed and the shank part.