Steel Product with Improved Weathering Characteristics in Saline Environment

Abstract

The present invention is related to a steel product of the weathering steel type, i.e. a product exhibiting increased corrosion resistance after having been exposed to the outside environment for a given time. According to the invention, the steel product is defined by a composition consisting of (in wt %):—Carbon between 0.03 and 0.2,—Manganese between 0.5 and 2,—Copper between 0 and 0.5,—Ti between 0 and 0.1,—Cr between 0 and 0.5,—Nickel between 0 and 0.2,—Niobium between 0 and 0.1,—Nitrogen between 0 and 0.01,—Sulphur between 0 and 0.01, Phosphor between 0 and 0.01,—Aluminium higher than 0 and maximum 1.5,—Silicon between 0.25 and 1.5, the balance being Fe and accidental impurities, and wherein the sum of the Al and Si levels is higher than about 0.85 wt %.

1 - 4 . (canceled) 
     
     
         5 . A steel product consisting of (in wt %):
 Carbon between 0.03 and 0.2   Manganese between 0.5 and 2   Copper between 0.2 and 0.4,   Titanium between 0.01 and 0.07,   Chromium between 0.2 and 0.5,   Nickel between 0.1 and 0.2,   Niobium between 0.02 and 0.1,   Nitrogen between 0 and 0.01,   Sulphur between 0 and 0.01,   Phosphor between 0 and 0.01,   Aluminium higher than 0 and maximum 1.5,   Silicon between 0.25 and 1.5,   
       the balance being Fe and accidental impurities, and wherein the sum of the Al and Si levels is higher than about 0.85 wt %. 
     
     
         6 . The steel product according to  claim 5 , comprising no Sn and no Sb. 
     
     
         7 . A steel product according to  claim 5 , said product being a sheet or beam. 
     
     
         8 . A steel product according to  claim 6 , said product being a sheet or beam. 
     
     
         9 . Use of a steel product according to  claim 5  as a product that exhibits an increase in corrosion resistance when exposed to a chlorine-rich environment. 
     
     
         10 . Use of a product according to  claim 6 , in saline outdoor conditions.