Patent ID: 9132567
Filing Date: 2015-09-15
Classification: B21D,B21J,B21K,B22F,B26F,C21D,C22C,Y10T

Abstract:
1. A method of making a shearing tool for use with a metalworking machine to cut a metal workpiece, the method comprising: fabricating a tool steel preform having a shank and a tip arranged along a longitudinal axis, the tool steel of the tip having a microstructure with a plurality of carbide bands or a plurality of alloy bands having a first density; thermo-mechanically processing the tip of the preform to define a first region in the tip such that the carbide bands or the alloy bands in the first region are not unidirectionally aligned and each of the carbide bands or each of the alloy bands in the first region has a positive angle of inclination over a first portion of the first region and a negative angle of inclination over a second portion of the first region, wherein the transition between the positive angle of inclination and the negative angle of inclination is continuous and the distance between the carbide bands or the alloy bands is reduced resulting in a second density greater than the first density, and wherein thermo-mechanically processing includes heating the tip to a processing temperature and, while the tip is at the processing temperature, applying a force to the tip to deform the tip in a direction that is generally parallel to the longitudinal axis to increase an area of a cross-sectional profile of the tip when viewed along the longitudinal axis and wherein, after deforming, the increased area of the cross-sectional profile of the deformed tip does not exceed an area of a cross-sectional profile of the shank when viewed along the longitudinal axis; and finishing the preform into the shearing tool with the first region of the tip defining a cutting edge at the intersection of a working surface for contacting the metal workpiece and a sidewall of the shearing tool, wherein the processing temperature is above the lower transformation temperature of the tool steel.