Abstract: A vitrified bond grindstone includes abrasive grains and a bonding material for fixing the abrasive grains, the bonding material includes a parent material containing SiO2 as a main constituent, a sintering assistant oxide, and ZnO, and the content of ZnO is 11 to 15 wt % in weight ratio based on the bonding material. Preferably, the content of the sintering assistant oxide is 20 to 29 wt % in weight ratio based on the bonding material.

Abstract: Disclosed herein is a grinding wheel including a wheel base to be fixed to a spindle, a plurality of abrasive members fixed to the wheel base, and a plurality of grinding water supply holes for supplying a grinding water to the abrasive members. Each abrasive member is formed as a segment abrasive having an outer surface extending downward from the lower surface of the wheel base so as to be inclined radially outward. The plural abrasive members are arranged annularly at given intervals. The plural grinding water supply holes are formed on the lower surface of the wheel base in the vicinity of the abrasive members so as to each correspond to the abrasive members in the condition where each grinding water supply hole lies on a line connecting the corresponding abrasive member and the axis of rotation of the wheel base.

Abstract: Disclosed herein is a grinding wheel including a wheel base to be fixed to a spindle, a plurality of abrasive members fixed to the wheel base, and a plurality of grinding water supply holes for supplying a grinding water to the abrasive members. Each abrasive member is formed as a segment abrasive having an outer surface extending downward from the lower surface of the wheel base so as to be inclined radially outward. The plural abrasive members are arranged annularly at given intervals. The plural grinding water supply holes are formed on the lower surface of the wheel base in the vicinity of the abrasive members so as to each correspond to the abrasive members in the condition where each grinding water supply hole lies on a line connecting the corresponding abrasive member and the axis of rotation of the wheel base.