Patent ID: 11911847
Assignee: ARCELORMITTAL
Field: Materials, metallurgy (Chemistry)
Classification: CPC B  C | IPC B  C

Claim 11:
12. The method as recited in claim 1, wherein, for at least one of the first and the second precoated steel sheets, the steel of the steel substrate comprises, by weight:
0.24%≤C≤0.38%
0.40%≤Mn≤3%
0.10%≤Si≤0.70%
0.015%≤AI≤0.070%
0%≤Cr≤2%
0.25%≤Ni≤2%
0.015%≤Ti≤0.10%
0%≤Nb≤0.060%
0.0005%≤B≤0.0040%
0.003%≤N≤0.010%
0.0001%≤S≤0.005%
0.0001%≤P<0.025%
wherein the titanium and nitrogen contents satisfy the following relationship:

Ti/N>3.42,

and the carbon, manganese, chromium and silicon contents satisfy the following relationship:, 2.6
     C
    
    +
    
     Mn
     5.3
    
    +
    
     Cr
     
      1
      ⁢
      3
     
    
    +
    
     Si
     
      1
      ⁢
      5
     
    
   
   ≥
   
    1
    .1
    %
   
  
  ,
 

the steel optionally comprising one or more of the following elements:
0.05%≤Mo≤0.65%
0.001%≤W≤0.30%
0.0005%≤Ca≤0.005%
a remainder being iron and impurities inevitably resulting from manufacturing.