During the use of the wire drawing die , when the abrasive grains are blunt, the abrasive grains partially or completely fall off from the abrasive tool due to the partial fragmentation of the abrasive particles themselves or the fracture of the bonding agent, and the abrasive material on the working surface of the abrasive tool continuously appears new cutting The cutting edge, or constantly revealing new sharp abrasive particles, enables the abrasive tool to maintain cutting performance within a certain period of time. This kind of self-sharpening of abrasive tools is the outstanding feature of abrasive tools compared with general tools.