Corrosion prevention of stainless steel

Abstract

A surface of an article of stainless steel becomes to have increased corrosion resistance by treatment with a heated aqueous hydroxylamine salt solution.

What is claimed is:  
     
         1 . A method for preventing an article of stainless steel from corroding, which comprises keeping the article in contact with a heated aqueous solution of a hydroxylamine salt.  
     
     
         2 . The method of    claim 1   , wherein the aqueous solution is heated to 50° C. or higher.  
     
     
         3 . The method of    claim 2   , wherein the aqueous solution is heated to a temperature in the range of 60° C. to 200° C.  
     
     
         4 . The method of    claim 1   , wherein the article is kept into contact with the heated solution for a period of 3 minutes or longer.  
     
     
         5 . The method of    claim 3   , wherein the article is kept into contact with the heated solution for a period of one hour or longer.  
     
     
         6 . The method of    claim 1   , wherein the heated solution contains the hydroxylamine salt in an amount of 0.2 to 50 weight %.  
     
     
         7 . The method of    claim 1   , wherein the hydroxylamine salt is hydroxylamine sulfate or hydroxylamine phosphate.  
     
     
         8 . The method of    claim 1   , wherein the article is a reaction vessel or a distilling apparatus.  
     
     
         9 . An article of stainless steel having a corrosion resistance surface which is treated with a heated aqueous solution of a hydroxylamine salt.