Patent ID: 8715838

Claim:
A surface-coated cutting tool including a base material, and a coat film formed on said base material, said surface-coated cutting tool having a chamfer portion where a rake face and a flank face meet, said coat film including at least one layer of a first coat layer, said first coat layer being an outermost surface layer of said coat film at said chamfer portion, said first coat layer at said chamfer portion having residual stress that exhibits a minimal value at a depth A within 2 μm from the surface of said chamfer portion, and that increasing continuously or stepwise as a function of depth in a further depth direction from said depth A, said minimal value of said residual stress being greater than or equal to −7 GPa and less than or equal to −1 G Pa, said first coat layer at a portion other than said chamfer portion having residual stress greater than the minimal value of said residual stress, said first coat layer at a portion other than said chamfer portion having residual stress that increases continuously or stepwise as a function of advance in a central direction of the rake face and a central direction of the flank face, and that is greater than or equal to 0 GPa and less than or equal to 2 GPa at said base material side, in the first coat layer at said chamfer portion, a region up to said depth A from the surface being a fine crystal texture region including crystals having an average grain size greater than or equal to 10 nm and less than or equal to 200 nm, and in said first coat layer, a region further deeper in a depth direction from said depth A at said chamfer portion, and a region other than said chamfer portion being a rough crystal texture region including crystals larger than the crystals in said fine crystal texture region.