Abrasive grain and method for producing it, grinding tool and method for producing it, grindstone for grinding and method for producing it, and grinding apparatus

摘要

An abrasive grain according to the present invention consists of porous particle material in which a large number of fine particles for cutting blade form gaps partly among them and bond loosely each other. The particles for cutting blade are produced by growing primary particles in secondary particles, which are formed by condensing a large number of primary particles, with heat treatment at a temperature of forming necks at bonding points among the primary particles. Therefore, it is possible to have stable processing for many hours with maintaining excellent quality very effectively.