To provide a method for producing a wire rod or a bar stock made of metal for cold shear cutting capable of increasing the hardness of the surface of a wire rod or a bar stock made of metal, attaining the reduction of the sagging of the cut pieces and improving the cuttability by shearing.
In the method for producing a wire rod or a bar stock made of metal for cold shear cutting, at least the surface of the wire rod 2 or bar stock formed into the shape of a strand is uniformly heat-treated by induction heating or electric resistance wire heating or direct electric heating, after that, the surface of the wire rod 2 or bar stock is uniformly subjected to rapid cooling by its dipping into water or oil or the spraying of water or oil or compressed air thereon, and the hardness of the surface to a position of 1/10 of the diameter or thickness from the surface is made higher than that of the inside.
SEKIYA TOSHIO
TAKAHASHI YUJI
