A composite metal sheet for use in making lightweight cookware or as a
food warming tray comprising a layer of aluminum roll bonded to a layer
of stainless steel defining a food-contacting surface on a first side.
The food warming tray embodiment also includes a layer of stainless steel
mesh roll bonded on a second side. A method of making a composite metal
sheet for cookware comprising the steps of: providing a roll pack of
ordered layers consisting of (a) a layer of Alclad aluminum, (b) a layer
of stainless steel foil, (c) a reusable plate or platen of stainless
steel, (d) a layer of stainless steel foil, and (e) a layer of Alclad
aluminum; heating the roll pack to a rolling temperature of about
725.degree.-775.degree. F., preferably about 750.degree. F.; and rolling
the heated roll pack in a rolling mill at a reduction of 10-20% in one
pass to provide two roll bonded composite sheets, the first composite
sheet comprising layers (a)-(b) above, and the second composite sheet
comprising layers (d)-(e) above with plate (c) being reusable, wherein
the plate of stainless steel is stationary relative to the layers of
stainless steel foil during rolling as the roll pack passes through the
mill, and wherein the plate transfers a bonding pressure to the aluminum
and foil layers without tearing or displacing the foil. The method for
making the food warming tray includes the addition of a layer of
stainless steel mesh applied to the outer surfaces of Alclad aluminum.
