Cubic boron nitride sintered material and use thereof for a cutting tool

摘要

The present invention relates to a cubic boron nitride sintered material having such a single-filament fiber-like structure that a shell member made of the cubic boron nitride sintered material constituted from cubic boron nitride particles that are bound by a binder phase made of nitride or carbide of at least one kind of metal element selected from among metals of groups 4, 5 and 6 of the periodic table covers the circumferential surface of a fiber-like core member made of the cubic boron nitride sintered material constituted from cubic boron nitride particles that are bound (a) by a binder phase made of carbide of at least one kind of metal element selected from among metals of groups 4, 5 and 6 of the periodic table in the case that the binder phase of the shell member is made of said nitride, or (b) by a binder phase made of nitride of at least one kind of metal element selected from among metals of groups 4, 5 and 6 of the periodic table in the case that the binder phase of the shell member is made of said carbide, a cutting tool and a method for cutting a workpiece.