Surface-coated cutting tool

Abstract

This surface-coated cutting tool is provided with: a lower layer consisting of a Ti compound layer; an intermediate layer consisting of an α-Al2O3 layer; and an upper layer consisting of a Zr-containing α-Al2O3 layer. The uppermost layer of the lower layer contains 0.5 to 3 at% of oxygen. In the frequency distribution made by counting inclination angles between the normal lines to the (0001) planes of Al2O3 grains of the intermediate layer and the normal line to the surface of a tool body, the maximum peak appears in an inclination angle range of 0 to 10 degrees and the ratio of the sum of frequencies falling in this inclination angle range is 50 to 70%. In the frequency distribution made by counting inclination angles between the normal lines to the (0001) planes of Al2O3 grains of the intermediate and upper layers and the normal line to the surface of the tool body, the maximum peak appears in an inclination angle range of 0 to 10 degrees and the ratio of the sum of frequencies falling in the inclination angle range is 75% or more. In at least 70 area% of the grains of the intermediate and upper layers, the inside of each grain is split by one or more crystal lattice interfaces represented by Σ3.

Description

technical field [0001] The present invention relates to a surface-coated cutting tool in which a hard coating layer exhibits excellent peeling resistance and chipping resistance during high-speed intermittent heavy cutting. Specifically, the present invention relates to a cutting process of various steels and cast irons under high-speed intermittent and heavy-duty cutting conditions in which high-speed intermittent and high-impact loads act on the cutting edge. Surface-coated cutting tools that exhibit excellent peeling resistance and chipping resistance, and exhibit excellent long-term wear resistance (hereinafter referred to as coated tools). [0002] This application claims priority based on Patent Application No. 2013-35566 filed in Japan on February 26, 2013 and Patent Application No. 2014-32483 filed in Japan on February 24, 2014, and uses the contents thereof in this specification. Background technique [0003] In the past, the following cladding tools have been know...

AI Technical Summary

Problems solved by technology

There is no problem when using the above-mentioned conventional coated tools for continuous cutting or intermittent cutting of steel and cast iron under normal conditions, but especially when used under high-speed intermittent heavy cutting conditions, the hard coating layer Ti compound layer to form the lower layer with Al 2 o 3 The adhesion strength between the upper layers composed of layers is insufficient, and abnormal damage such as peeling and chipping between the upper layer and the lower layer occurs, thereby reaching the service life in a relatively short period of time. This is the current situation of cutting devices.

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