Abstract: A method of manufacturing composite cookware or bakeware comprising the steps of (a) providing a bonded multi-layer composite sheet of material having at least one layer of an aluminum or aluminum alloy material; (b) forming a cookware vessel of a desired configuration having the aluminum or aluminum alloy layer exposed at least at an edge portion of the formed cookware vessel; and (c) treating at least the exposed edge of aluminum or aluminum alloy by a micro arc oxidation process to form an Al2O3 coating on at least the exposed edge of aluminum or aluminum alloy whereby chemical corrosion/erosion of the exposed edge by caustic cleaning agents is prevented.

Abstract: A method of making a composite metal material comprising the steps of providing two outer layers of copper pre-bonded to a pure aluminum such as 1100 series aluminum or to an aluminum alloy such as 3003 aluminum alloy; providing a core layer of alclad aluminum, comprising a composite having a core of aluminum alloy pre-bonded to outer layers of substantially pure 1100 series aluminum; placing the outer layers of copper pre-bonded material on either side of the alclad core layer such that the aluminum layer carried by each copper layer is facing the alclad core layer to form a stacked pack; heating the stacked pack assembled in step (c) to a suitable rolling temperature, such as about 650° F.; and hot rolling the stacked pack in a rolling mill at incremental reductions to roll bond the layers to a desired finished thickness.

Abstract: A method of making cookware and bakeware having a stick resistant and mar resistant cook surface comprising the steps of providing a cooking utensil having a cook surface, and cryogenically treating the cooking utensil at one or more selected temperatures comprising −100° F. to −300° F. or lower to harden said cook surface. The cooking utensil may have a bare metal cook surface, or it may be coated with a stick resistant coating such as one of a PTFE, metal nitride or sulfide coating or combinations thereof prior to the cryogenic hardening treatment.

Abstract: A method of joining dissimilar metals includes the steps of applying a thin layer of pure aluminum to a surface of at least one of the dissimilar metals to be joined. The pure aluminum is applied by electroplating or by a PVD technique to prevent formation of oxides or intermetallic aluminum compounds in the pure aluminum layer. A barrier layer of chromium may also be applied between the substrate metal and the pure aluminum layer in high temperature applications such as where subsequent welding is anticipated to prevent the formation of harmful intermetallic compounds which may otherwise occur between the substrate and the pure aluminum layer. The sheets or slabs of dissimilar metals are then roll bonded by hot rolling with the aluminum layer forming an excellent diffusion bond therebetween. Difficult to bond metals such as copper, brass, carbon steel, titanium, certain aluminum alloys and zinc may be roll or press bonded in this way.

Abstract: A method of making cookware and bakeware having a stick resistant and mar resistant cook surface comprising the steps of providing a cooking utensil having a cook surface, and cryogenically treating the cooking utensil at one or more selected temperatures comprising −100° F. to −300° F. or lower to harden said cook surface. The cooking utensil may have a bare metal cook surface, or it may be coated with a stick resistant coating such as one of a PTFE, metal nitride or sulfide coating or combinations thereof prior to the cryogenic hardening treatment.

Abstract: A method for making a stick resistant cook surface or cooking vessel having the stick resistance in which a hard substrate metal is buffed/polished to a high luster surface finish of less than 20 micro inches and then coated with a layer of zirconium nitride. The method further includes the step of polishing a stamped blank to the desired surface smoothness prior to the drawing/shaping step to provide a stick resistant surface in cooking vessels having side walls, such as pots and pans, which are otherwise difficult to buff in the interior due to the side wall geometry.

Abstract: A 5-ply composite metal product for the manufacture of cookware is provided which contains a relatively thick copper core having relatively thin layers of pure aluminum bonded between outer layers of stainless steel. The cooking vessels made therefrom may contain a decorative groove or skived ring around a perimeter of the vessel, formed by machining away the outer layers of stainless steel and pure aluminum to visually expose the copper core.

Abstract: A composite griddle plate is provided having a heavy copper core which is diffusion bonded to one or more outer plates of stainless steel, carbon steel or titanium. The copper cored composite is made by explosion bonding the outer metal plates to the copper core to achieve diffusion bonding followed by multi-pass, small, incremental reduction passes in a hot rolling mill conducted within a narrowly controlled temperature range falling within the overlapping hot working range of the copper core and the dissimilar metal of the outer layers.