Grinding wheel and grinding method

Abstract

A grinding wheel for grinding a workpiece has an annular wheel base and a plurality of grinding stones arrayed in an annular pattern on a side of one surface of the wheel base. The grinding stones each have a base portion having a mounting surface where the base portion is mounted on the wheel base, and a wear-accelerated portion that has a grinding surface to be brought into contact with the workpiece and is more prone to wearing than the base portion.

What is claimed is: 
     
         1 . A grinding wheel for grinding a workpiece, comprising:
 an annular wheel base; and   a plurality of grinding stones arrayed in an annular pattern on a side of one surface of the wheel base, wherein   the grinding stones each include
 a base portion having a mounting surface where the base portion is mounted on the wheel base, and 
 a wear-accelerated portion that has a grinding surface to be brought into contact with the workpiece and is more prone to wearing than the base portion. 
   
     
     
         2 . The grinding wheel according to  claim 1 , wherein the wear-accelerated portion has a higher brittleness than that of the base portion. 
     
     
         3 . The grinding wheel according to  claim 1 , wherein the wear-accelerated portion has a lower Vickers hardness than that of the base portion. 
     
     
         4 . The grinding wheel according to  claim 1 , wherein
 the wear-accelerated portion is made from a same material as that of the base portion, and   a plurality of grooves are formed on a side of the grinding surface of the wear-accelerated portion.   
     
     
         5 . The grinding wheel according to  claim 1 , wherein the wear-accelerated portion is made from a same material as that of the base portion and has a shape with a cross-sectional area that is parallel to the mounting surface and is progressively reduced toward the grinding surface. 
     
     
         6 . The grinding wheel according to  claim 1 , wherein the wear-accelerated portion has a higher porosity than that of the base portion. 
     
     
         7 . The grinding wheel according to  claim 1 , wherein the wear-accelerated portion has a thickness of 5 μm or greater and 15 μm or smaller in a direction from the grinding surface toward the base portion. 
     
     
         8 . A grinding method of a workpiece with a grinding wheel comprising:
 grinding a surface of the workpiece with a wear-accelerated portion of the grinding wheel, the grinding wheel includes an annular wheel base and a plurality of grinding stones arrayed in an annular pattern on a side of one surface of the wheel base, the grinding stones each include a base portion having a mounting surface where the base portion is mounted on the wheel base and the wear-accelerated portion that has a grinding surface to be brought into contact with the workpiece and is more prone to wearing than the base portion, and,   after the wear-accelerated portion has been lost, grinding the workpiece by the base portion.