Corrosion resistant, colored stainless steel and method of making same
AssigneeThe Louis Berkman Company
InventorsJay F. Carey, II, Nicholas R. Hesske
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Abstract
A colored, corrosion resistant architectural material having improved corrosion-resistant properties wherein the material includes stainless steel which is coated with a tin and the tin coated material is post-treated with an oxidizing solution to remove the tin coating to expose a barrier which includes an alloy of chromium, iron and tin. The barrier exhibits excellent corrosion resistance especially with respect to chlorine and has a dark grey or earth tone grey color.
Claims23
A corrosion resistant architectural material exhibiting excellent corrosion resistance comprising a stainless steel strip having an intermetallic surface layer formed by passing said stainless steel strip through a bath of molten tin at a temperature greater than 449.degree. F. at a speed of less than 150 ft/min to produce a tin layer of less than 0.002 inch over said intermetallic surface layer and removing said tin coating from the surface of said stainless steel strip to expose said intermetallic layer with an oxidizing solution.
A method of providing a colored protective layer on a ferrous strip surface by a continuous process, said method comprising the steps of:
- (a) pre-treating said ferrous strip for removing oxides from the surface of said strip;
- (b) providing a tin coating of less than about 0.002 inch thickness on said surface to create an intermetallic alloy layer between said strip surface and said tin coating, said alloy layer containing chromium, tin and iron, said tin coating provided by passing said strip at less than 150 ft/min through a molten bath of tin which is maintained at a temperature of at least 449.degree. F.;
- (c) cooling said tin coated ferrous strip;
- (d) removing said tin coating with an oxidizing solution to expose said intermetallic layer.
Dependencies are inferred from the claim text.