Patent ID: 7434439

Claim:
A method of forming a workpiece comprising (a) providing a tool for metal forming and a workpiece, wherein the workpiece comprises metal and has an initial shape; (b) placing the workpiece and the tool in contact, applying force to the tool and/or the workpiece, and moving the tool and/or the workpiece to effect a change in the initial shape of the workpiece by forming wherein the workpiece softens under said force; and (c) providing a jet of cryogenic fluid and impinging essentially all of the jet of cryogenic fluid on an external surface of the tool, wherein essentially no cooling of the workpiece is effected by impingement of said jet of cryogenic fluid, and the geometric average temperature of the tool is less than the geometric average temperature of the workpiece; and the tool is cooled such that it retains hardness and strength; and further wherein said method of forming is selected from the group consisting of contour and profile roll forming, power spinning, roll forging, orbital forging, shoe-type pinch rolling, alligator shearing, guillotine shearing, punch parting, rotary shearing, line shearing, slitting, wire and rod drawing, tube drawing, moving mandrel drawing, punch drawing, moving insert straightening, die and punch press bending, hammer forming, and die forging.