Apparatus for shear-cutting a stack of amorphous steel strips

Abstract

For shear-cutting a stack of thin strips of amorphous steel along a cutting plane that extends transversely of the stack, an apparatus that comprises two blades that are positioned at the start of a cutting operation on opposite sides of the stack is utilized. Each of the blades has a first surface for engaging one side of the stack and a second surface extending transversely of the first surface and generally parallel to said cutting plane and intersecting the first surface at a corner. The first surface of each blade is disposed at a predetermined rake angle with respect to a reference plane extending through a point on the corner of the blade and normal to said cutting plane. The apparatus is further characterized by the following features that cooperate to impart to the blades an exceptionally high resistance to wear: (i) the sum of the rake angles is of a negative value and between 5 and 35 degrees, and (ii) both blades are of a cemented carbide cutting material that consists essentially of tungsten carbide particles and cobalt particles compacted under high pressure and sintered at a temperature exceeding the melting point of the cobalt, the tungsten carbide particles being, on average, of submicron size and the cobalt constituting more than 15 percent and about 16 percent by weight of the cutting material.