SILICON NITRIDE CUTTING TOOL

摘要

PURPOSE:To provide a cutting tool excellent in the defect resistance and also excellent in the productivity. CONSTITUTION:A silicon nitride cutting tool comprising a silicon nitride sintered product produced from alpha-silicon nitride and beta'-sialon is characterized in that the average crystal particle diameter of the alpha-silicon nitride is <=0.5nm and that the average crystal particle diameters of the beta'-sialon in the major axis and minor axis directions are 2.0-5.0mum and <=0.5mum, respectively.