Patent ID: 8220693
Filing Date: 2012-07-17
Classification: B22F,B23K,C22C,C23C,Y10T

Abstract:
1. A method for selectively modifying at least a portion of a metal sheet metal forming die body by creating a composite, lubricious layer of predetermined depth in a surface of the body intended for contact with the sheet metal, the surface for creating such layer protruding beyond the intended die body surface; the method comprising: forming indentations protruding in the surface of the body in which the composite layer is to be formed, the indentations being sized and spaced to accept and store a predetermined quantity of particles of a desired material for incorporation of the material in the surface of the die body; the surface protruding beyond the intended die body surface to provide excess body material for shaping and suitably finishing the modified surface; placing a predetermined quantity of at least one particulate material in the indentations in the surface of the body; using a friction stir tool with a pin, the pin having a length and a diameter, to frictionally heat and mix the particulate matter in the indentations with adjacent metal of the body and traversing the friction stir tool across the body to mix the particulate material with the material of the body to a depth substantially equal to the length of the pin, such mixture constituting a precursor of the intended composite layer; and then performing one or more of machining, grinding and polishing on at least the modified portion of the precursor surface to form the die body and render, on the modified surface portion of the die body, a suitably shaped and lubricious surface for sheet metal contact.