Abstract: A system for developing a metal workpiece in which the center and the periphery have different properties. The workpiece is processed to put it into a first metallurgical condition. Then, a portion of the periphery is dipped into a molten salt bath and the workpiece is rotated so that the periphery is converted to a second metallurgical condition by the heat of the salt bath.

Abstract: Two pieces of metal are bonded together at a surface by placing the two pieces into contact at the surface and forging the two pieces in a die which causes substantial displacement of the metal originally at the surface in a direction parallel to and outwardly from the edges of the surface. In this way, many of the defects which are potentially present at the original surface are displaced with moving metal away from the original contact between the two pieces of metal into sacrificial ribs and the remaining defects are exposed to significant strain. A portion of the displaced metal which contains many of the defects and which forms the sacrificial ribs is removed from the resulting bonded work piece as the sacrificial ribs are removed from the work piece. The result is a bond with superior properties and with a bond surface which can be located very precisely.