Abstract: The surface-coated member 1 is constituted by coating the surface of the base body 2, made of such a material as cemented carbide or cermet, with the hard coating layer 3 that comprises at least one TiCN layer 4 and the Al2O3 layer 6 formed on the surface of the TiCN layer 4, wherein the TiCN layer 4 is constituted from stringer-like TiCN crystal grown in a direction perpendicular to the base body 2 and mean crystal width w1 of the TiCN layer 4 on the Al2O3 layer 6 side is made larger than mean crystal width w2 on the base body 2 side. This surface-coated member, as a cutting tool, shows excellent breakage resistance and high wear resistance with a long service life, where strong adhesion force of the hard coating layer can be maintained without experiencing peel-off between the TiCN layer and the Al2O3 layer even in cutting operations under harsh cutting conditions, such as intermittent cutting operation where the cutting edge is subject to strong impact.

Abstract: There is provided a cemented carbide comprising a hard phase component which comprises a tungsten carbide (WC) and at least one selected from carbides, nitrides and carbonitrides of metals of the groups 4a, 5a and 6a in the periodic table; and a binder phase component comprising at least one of iron-group metals, wherein the surface region of the cemented carbide has 90–98% of the minimum hardness as compared with internal hardness, thereby having high hardness and toughness which is suitable to using as a cutting tool.

Abstract: There is provided a cemented carbide comprising a hard phase component which comprises a tungsten carbide (WC) and at least one selected from carbides, nitrides and carbonitrides of metals of the groups 4a, 5a and 6a in the periodic table; and a binder phase component comprising at least one of iron-group metals, wherein the surface region of the cemented carbide has 90-98% of the minimum hardness as compared with internal hardness, thereby having high hardness and toughness which is suitable to using as a cutting tool.

Abstract: There is provided a cemented carbide comprising a hard phase component which comprises a tungsten carbide (WC) and at least one selected from carbides, nitrides and carbonitrides of metals of the groups 4a, 5a and 6a in the periodic table; and a binder phase component comprising at least one of iron-group metals, wherein the surface region of the cemented carbide has 90-98% of the minimum hardness as compared with internal hardness, thereby having high hardness and toughness which is suitable to using as a cutting tool.

Abstract: The surface-coated member 1 is constituted by coating the surface of the base body 2, made of such a material as cemented carbide or cermet, with the hard coating layer 3 that comprises at least one TiCN layer 4 and the Al2O3 layer 6 formed on the surface of the TiCN layer 4, wherein the TiCN layer 4 is constituted from stringer-like TiCN crystal grown in a direction perpendicular to the base body 2 and mean crystal width w1 of the TiCN layer 4 on the Al2O3 layer 6 side is made larger than mean crystal width w2 on the base body 2 side. This surface-coated member, as a cutting tool, shows excellent breakage resistance and high wear resistance with a long service life, where strong adhesion force of the hard coating layer can be maintained without experiencing peel-off between the TiCN layer and the Al2O3 layer even in cutting operations under harsh cutting conditions, such as intermittent cutting operation where the cutting edge is subject to strong impact.

Abstract: There is provided a cemented carbide comprising a hard phase component which comprises a tungsten carbide (WC) and at least one selected from carbides, nitrides and carbonitrides of metals of the groups 4a, 5a and 6a in the periodic table; and a binder phase component comprising at least one of iron-group metals, wherein the surface region of the cemented carbide has 90-98% of the minimum hardness as compared with internal hardness, thereby having high hardness and toughness which is suitable to using as a cutting tool.