| 摘要 |
PURPOSE:To obtain the titled cutting tools made of WC-base sintered hard alloy excelling in breaking resistance and wear resistance by providing a WC- base sintered hard alloy substrate with a matrix having a specific structure and by constituting the matrix of specific WC-base sintered hard alloy and soft massive phase. CONSTITUTION:In the cutting tools of surface-treated WC-base sintered hard alloy having a hard coating layer on the surface of the WC-base sintered hard alloy substrate, the substrate has a structure made by uniformly distributing in the matrix the soft massive phase having a minimum diameter of >=30mu in a spotted state. Further, the above matrix is constituted of the WC-base sintered hard alloy consisting of 4-12wt% Co, 2-30wt% of 1 or >=2 kinds among the carbides and nitrides of the group VIa metals and the solid solutions of >=2 kinds of the above, and the balance WC with inevitable impurities and also the above soft massive phase is constituted of a composition consisting of 5-25wt% Co and the balance WC with inevitable impurities. |
