Steel for high-strength components made of bands, sheets or tubes having excellent formability and particular suitability for high-temperature coating processes

Abstract

A steel for high-strength components including bands, sheets or pipes having excellent formability and particular suitability for high-temperature coating processes above Ac 3 (about 900° C.) is disclosed. The steel includes the following elements (contents in % by mass): C 0.07 to ≦0.15, Al≦0.05, Si≦0.80, Mn 1.60 to ≦2.10, P≦0.020, S≦0.010, Cr 0.50 to ≦1.0, Mo 0.10 to ≦0.30, Ti min 48/14×[N], V 0.03 to ≦0.12, B 0.0015 to ≦0.0050, with the balance iron including usual steel-accompanying elements.

1 .- 13 . (canceled) 
     
     
         14 . A steel for high-strength components of bands, sheets or pipes, comprising by mass percent: 
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   C 
                   0.07 to ≦0.15 
                 
                     
                   Al 
                   ≦0.05 
                 
                     
                   Si 
                   ≦0.80 
                 
                     
                   Mn 
                   1.60 to ≦2.10 
                 
                     
                   P 
                   ≦0.020 
                 
                     
                   S 
                   ≦0.010 
                 
                     
                   Cr 
                   0.50 to ≦1.0 
                 
                     
                   Mo 
                   0.10 to ≦0.30 
                 
                     
                   Ti min   
                   48/14 × [N] 
                 
                     
                   V 
                   0.03 to ≦0.12 
                 
                     
                   B 
                   0.0015 to ≦0.0050, 
                 
                     
                     
                 
             
                
               
               
                
                
                
                
                
                
                
                
                
                
                
                
               
            
           
         
       
       with balance iron, including usual steel-accompanying elements. 
     
     
         15 . The steel of  claim 14 , having a C-content of 0.08 to ≦0.10%. 
     
     
         16 . The steel of  claim 14 , having a Si-content of ≦0.30%. 
     
     
         17 . The steel of  claim 14 , having a Mn-content of 1.80 to ≦2.0%. 
     
     
         18 . The steel of  claim 14 , having a Cr-content of 0.70 to ≦0.80%. 
     
     
         19 . The steel of  claim 14 , having a Mo-content of 0.15 to ≦0.25%. 
     
     
         20 . The steel of  claim 14 , having a Ti-content of 0.02 to ≦0.03%. 
     
     
         21 . The steel of  claim 14 , having a V-content of 0.05 to ≦0.10%. 
     
     
         22 . The steel of  claim 14 , having a B-content of 0.0025 to ≦0.0035%. 
     
     
         23 . The steel of  claim 14  for application in a high-temperature coating process above Ac 3  (about 900° C.). 
     
     
         24 . A component formed from a readily formable band, sheet or tube made of a steel comprising, in mass percent: 
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   C 
                   0.07 to ≦0.15 
                 
                     
                   Al 
                   ≦0.05 
                 
                     
                   Si 
                   ≦0.80 
                 
                     
                   Mn 
                   1.60 to ≦2.10 
                 
                     
                   P 
                   ≦0.020 
                 
                     
                   S 
                   ≦0.010 
                 
                     
                   Cr 
                   0.50 to ≦1.0 
                 
                     
                   Mo 
                   0.10 to ≦0.30 
                 
                     
                   Ti min   
                   48/14 × [N] 
                 
                     
                   V 
                   0.03 to ≦0.12 
                 
                     
                   B 
                   0.0015 to ≦0.0050, 
                 
                     
                     
                 
             
                
               
               
                
                
                
                
                
                
                
                
                
                
                
                
               
            
           
         
       
       with balance iron, including usual steel-accompanying elements, wherein the component is, after forming, heat-treated at a temperature above Ac 3  (about 900° C.) and has after cooldown a minimum yield strength of 450 MPa. 
     
     
         25 . The component of  claim 24 , wherein the heat treatment includes enameling with one or more firings. 
     
     
         26 . The component of  claim 24 , wherein the heat treatment includes a metallic coating. 
     
     
         27 . The component of  claim 26 , wherein the coating is a zinc-plating. 
     
     
         28 . A method of making a component, comprising the steps of:
 forming a structure selected from the group consisting of band, sheet, and tube into a shape;   heat-treating the structure at a temperature above Ac 3  (about 900° C.); and   allowing the structure to cool down to produce a component with a minimum yield strength of 450 MPa.