| 摘要 |
To provide a surface-coated cemented carbide insert which exhibits excellent chipping resistance and thermoplastic deformation resistance, in an interrupted heavy cutting process of steel or cast iron in which an impulsive and intermittent high load acts on a cutting edge. Provided is a surface-coated cemented carbide insert which is obtained by containing at least WC powder and Co powder as raw materials, including a WC-based cemented carbide obtained by forming and sintering mixed raw materials containing at least any of (a) Zr compound powder, Nb compound powder, and Ta compound powder, (b) complex compound powder of Nb and Ta, and Zr compound powder, (c) complex compound powder of Nb, Ta, and Zr, (d) complex compound powder of Nb, Zr, and Ta compound powder, and (e) complex compound powder of Ta and Zr, and Nb compound powder, as essential powder components, as a substrate, and forming a hard coating layer on the substrate by vapor deposition, in which a Co enrichment surface region is formed in a substrate surface, Co content in the Co enrichment surface region satisfies to be between 1.30 and 2.10 (herein, in a mass ratio) of Co content in cemented carbide, and total content of Nb and Ta in the Co enrichment surface region is between 0.025 and 0.085 (herein, in a mass ratio) of the Co content in Co enrichment surface region. |
