| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface-coated cutting tool exhibiting an excellent chipping resistance in high-speed high cut-in intermittent cutting of alloy steel where a high load acts on a cutting blade.SOLUTION: In a surface-coated cutting tool where the surface of a tool base is coated with an α type aluminum oxide layer directly or via the underlayer by the sol-gel method using a sol with Ti oxide fine particles previously added, a Ti compound uniformly dispersed in the aluminum oxide layer including one or more kinds of a Ti carbide, a nitride and a carbonitride, an area ratio of the Ti compound occupied in the α type aluminum oxide layer being a 20 to 70 area% of the longitudinal cross-section observation range of the α type aluminum oxide layer, the average grain size of the Ti compound being 10 to 200 nm, and an average intersection number density with the longitudinal cross section of the α type aluminum oxide layer divided into grid lines of 0.2 μm squared to make an interface between the α type aluminum oxide crystal grain and the Ti compound cross the grid lines being 50 to 150 pieces/μmin either of a vertical direction to the tool base surface and a parallel direction with the tool base surface.SELECTED DRAWING: Figure 1 |
