Abstract: An electrocontact discharge dressing for a grinding wheel is performed by contacting a grinding surface of the grinding wheel, which is formed by bonding super hard diamond grains with a metal-based bond, with a pair of electrodes made of steels for general structure, rotating the grinding wheel for grinding a contact surface of each of the pair of electrodes with the rotating grinding wheel to form flow type chips in the contact surface, and applying a voltage to the pair of electrodes to generate an electric discharge from the flow type chips toward the metal-based bond of the rotating grinding wheel whereby the metal-based bond is molten due to heat of the electric discharge, and removed from the grinding wheel to enable dressing of the grinding wheel with excellent dressing efficiency.

Abstract: A grinding tool has diamond superabrasive grains as the abrasive and a bond to retain the abrasive grains. The bond is made of organic polymer or metal and contains as a filler both a solid film-forming lubricant and finely divided diamond superabrasive grains having a grain size smaller than one-third that of the diamond superabrasive grains as the abrasive. The grinding tool of this invention is suitable for grinding a hard cutting material such as cutting tools made of titanium nitride cermet and exhibits outstanding cutting performance and durability.