Cookware with copper bonded layer
AssigneeAll-Clad Metalcrafters LLC
InventorsWilliam A. Groll, Bruce W. Perry
Life of this patent
Estimating the term…
Abstract
Provided is an article of cookware and a method of making the same. The cookware has at least one stainless steel layer and at least one copper layer metallurgically bonded directly to the at least one stainless steel layer via solid state bonding. The at least one stainless steel layer may be a ferritic stainless steel layer, and the at least one copper layer may be a grain stabilized copper. The at least one stainless steel layer may be made from a 400 series stainless steel, such as a 436 stainless steel alloy, a 439 stainless steel alloy, or a 444 stainless steel alloy. The at least one copper layer may be made from a high purity, oxygen free copper alloy, such as a C101 copper alloy, a C102 copper alloy, or a C107 copper alloy.
Claims20
Cookware having a multi-layer, solid state bonded composite wall structure, the cookware comprising:
- at least one stainless steel layer;
- and
- at least one copper layer metallurgically bonded to the at least one stainless steel layer via solid state bonding at a temperature between 625° C. and 675° C. (1157° F. and 1250° F.) and a static pressure between 5,000 psi and 20,000 psi (350 kg/cm2 to 1,400 kg/cm2),
- wherein the at least one copper layer is any high purity, deoxidized copper or copper alloy having some residual hardness or temper from fully annealed up to ½ hard that exhibits controlled grain growth properties during solid state bonding,
- wherein the at least one stainless steel layer is made from a ferro-magnetic stainless steel.
Cookware having a three-layer, bonded composite wall structure, the cookware comprising:
- an upper stainless steel layer and a lower stainless steel layer;
- and a copper layer between the upper stainless steel layer and the lower stainless steel layer, the copper layer metallurgically bonded directly to the upper stainless steel layer and the lower stainless steel layer,
- wherein the upper stainless steel layer and the lower stainless steel layer are made from a ferritic stainless steel, and wherein the copper layer is made from any high purity, deoxidized copper or copper alloy having some residual hardness or temper from fully annealed up to ½ hard that exhibits controlled grain growth properties during solid state bonding, and
- wherein a ring-shaped portion of the lower stainless steel layer is removed to visually expose a portion of the copper layer.
Dependencies are inferred from the claim text.