Excellent diamond-coated cemented carbide drill to wear resistance

摘要

PROBLEM TO BE SOLVED: To provide a drill made of diamond-coated cemented carbide having not only excellent chipping resistance but also excellent wear resistance in a long-term use in the overlap drilling or the like of CFRP and Al.;SOLUTION: A drill made of diamond-coated cemented carbide includes a base body of WC-based cemented carbide mainly made of WC and Co, and containing 3-15 mass% of Co while a diamond film of an average film thickness of 5-30 μm is coated on the base body. A ratio of h1/h2 is ≥1.2 and ≤2.0 where h1 denotes the film thickness of an outer circumferential part of a cutting edge of the drill, and h2 denotes the film thickness of a chisel edge. Preferably, a value of w2 is ≥15 cm^-1, and ≤25 cm^-1, and a ratio w1/w2 is ≥0.5 and ≤0.9 where w1, w2 denote the half peak width of the peak around 1,333 cm^-1 at the Raman spectrometry of the outer circumferential part of the cutting edge and the chisel edge, respectively. More preferably, the ratio σ2/σ1 is ≥0.6 and ≤0.9 where σ1, and σ2 denote values of the compressive residual stress in the outer circumferential part of the cutting edge and the chisel edge, respectively.;COPYRIGHT: (C)2013,JPO&INPIT