A grinding wheel having a tool portion formed by firmly fixing diamond grains
to
an end face of a cup-shaped core by brazing. A circumferentially continuous groove
is formed in a substantially central portion of the end face of the core. The abrasive
grains are firmly fixed to an end face portion excluding regions near an outer
rim and near an inner rim of the end face and near the boundaries with the groove
under the condition that, with respect to all the abrasive grains, skirts of a
brazing material layer for holding the abrasive grains have a length one or more
times an average grain size of the abrasive grains. The provision of the groove
in the end face of the core can enhance the capability of ejecting chips that occur
during machining; besides, chips can be captured in the groove to preclude the
occurrence of scratches resulting from the chips. Moreover, sufficient lengths
of skirts of the brazing material layer are secured for all the abrasive grains
arranged on the end face of the core, which improves the force for holding the
abrasive grains and avoids grain fall-out during machining.
