SURFACE COATED CEMENTED CARBIDE-MADE CUTTING TOOL HAVING HARD COATING LAYER EXHIBITING EXCELLENT WEAR RESISTANCE IN HIGH-SPEED CUTTING SOFT MATERIAL HARD TO WORK

摘要

PROBLEM TO BE SOLVED: To provide a surface coated cutting tool having a hard coating layer exhibiting excellent wear resistance in high-speed cutting soft material hard to work.;SOLUTION: In this surface coated cutting tool, the following hard coating layer is formed on the surface of a cemented carbide base. The hard coating layer includes: (a) a surface layer formed of Cr boride layer; and (b) a wear resisting hard layer formed of a compound nitride layer of Ti, Al and Si, which satisfies a composition formula: (Ti_1-(X+Y)Al_XSi_Y)N (wherein 0.45≤X≤0.65, 0.01≤Y≤0.10, and 0.50≤X+Y≤0.70 by atomic ratio). In the surface layer, the surface roughness of a cutting face at least including a cutting edge ridge part and a flank part is set at 0.2 μm or less Ra by injecting a polishing liquid mixed with aluminum oxide fine grains as an injection abrasive by a wet blast to polish under the coexistence of pulverized Cr nitride fine grains made by wet blasting the abrasive layer and aluminum oxide fine grains as the injection abrasive in the state where the abrasive layer formed of Cr nitride layer is formed on the whole surface of the surface layer by vapor deposition.;COPYRIGHT: (C)2007,JPO&INPIT