A TOOL OF A SURFACE-COATED BORON NITRIDE SINTERED COMPACT

摘要

The object of the present invention is to provide a cutting tool con-sisting of a suface-coated high pressure phase type boron nitride sinter ed compact, having a markedly improved adhesive strength of a hard coated layer to a cBN sintered compact substrate. The feature consists in a surface-coated boron nitride sintered compact tool, in which at least a part of the tool edge related with cutting is base d on a substrate of a high pressure phase type boron nitride, and a surface- coated layer is allowed to be present on the surface thereof, the said surface-coat ed layer comprising an intermediate layer being present in discontinuous manner to the interface of the said high pressure phase boron nitride sintered compact substrate and a hard coated layer formed further thereon or in the form of dispersed particles, the said intermediate layer consisting of at least one element selected from the Group 4a, 5a and 6a of Periodic Table.