CBN SINTER AND CBN SINTER TOOL

摘要

This invention provides cBN sinter which is excellent in defect loss resistance and abrasion resistance in poor-machinable centrifugal casting cast iron machining. The cBN sinter comprises by volume not less than 50% and not more than 90% or not less than 40% and not more than 85% of a cBN component. The cBN sinter is characterized by comprising by volume not less than 9% and not more than 50% of alumina and zirconia and having a zirconia/alumina weight ratio of not less than 0.1 and not more than 4. A tool, in which the cBN sinter has been used in a cutting related part, is superior in poor-machinable centrifugal casting cast iron machining to the conventional cBN sinter tool by virtue of excellent strength, hardness, and toughness.