STOCK FOR WIRE DRAWING DIE AND WIRE DRAWING DIE MADE OF THIS STOCK

摘要

PURPOSE:To obtain a die having a long wire drawing life by using synthetic diamond Ib type single crystal containing a specific amount of nitrogen in crystal and having a plane vertical to the wire drawing direction as a specific cleavage plane. CONSTITUTION:Synthetic diamond Ib type single crystal containing 20-400ppm of nitrogen in crystal is used as a drawing die stock A. At least one of two planes vertical to the wire drawing direction is made a (111) cleavage plane 1. The surface roughness of the cleavage plane is made <=100mum. At least a side face other than the cleavage surface 1 is made an unground surface or it is not a growth surface but the surface roughness is made 5-100mum. The angle between the center line of the wire drawing hole 3 of the die and the cleavage surface 1 is made 87-93 deg.. Consequently, it is possible to obtain die stock for in variance.