Patent ID: 7761971

Claim:
A process for forming an article of cookware, the process comprising the steps of: a) providing at least one substantially planar sheet comprising one or more layers of metal, b) deforming the metal sheet to form a preform having a bottom surface and surrounding sides extending upward therefrom to form a fluid containing vessel with an interior surface and an exterior surface, the bottom surface having a first diameter, c) introducing the preform in an impact bonding press having an interior surface die and an exterior surface die, the fluid retaining interior surface of the preform facing said interior surface die, wherein; i) the exterior surface die has a convex shape, and ii) the interior surface die has a shape that is selected from the group consisting of substantially planar and convex, d) providing a medallion having a second diameter substantially less than the first diameter between the bottom of the preform and the exterior surface die, e) impacting the preform between the interior and exterior dies to form a cooking vessel such that the contour of the interior surface die is imparted to the interior bottom surface of the cooking vessel and a slightly concave shape is imparted to the outside bottom surface of the preform as the medallion is embedded therein by said step of impacting.