US 12,139,782 B2
Method for the manufacturing of liquid metal embrittlement resistant zinc coated steel sheet
Anirban Chakraborty, Chesterton, IN (US); Hassan Ghassemi-Armaki, Schererville, IN (US); Pascal Bertho, Maizieres-les-Metz (FR); and Christian Allely, Metz (FR)
Assigned to ArcelorMittal, Luxembourg (LU)
Filed by ArcelorMittal, Luxembourg (LU)
Filed on Dec. 30, 2022, as Appl. No. 18/091,794.
Application 18/091,794 is a division of application No. 16/759,253, granted, now 11,566,310, previously published as PCT/IB2018/058991, filed on Nov. 15, 2018.
Claims priority of application No. PCT/IB2017/057196 (WO), filed on Nov. 17, 2017.
Prior Publication US 2023/0137133 A1, May 4, 2023
Int. Cl. C22C 38/58 (2006.01); C21D 1/76 (2006.01); C21D 9/46 (2006.01); C21D 9/56 (2006.01); C22C 38/02 (2006.01); C22C 38/06 (2006.01); C22C 38/44 (2006.01); C22C 38/48 (2006.01); C22C 38/50 (2006.01); C22C 38/54 (2006.01); C23C 2/02 (2006.01); C23C 2/06 (2006.01); B23K 11/11 (2006.01); B23K 35/02 (2006.01); B23K 35/28 (2006.01); B23K 35/30 (2006.01); B23K 103/04 (2006.01)
CPC C22C 38/58 (2013.01) [C21D 1/76 (2013.01); C21D 9/46 (2013.01); C21D 9/561 (2013.01); C22C 38/02 (2013.01); C22C 38/06 (2013.01); C22C 38/44 (2013.01); C22C 38/48 (2013.01); C22C 38/50 (2013.01); C22C 38/54 (2013.01); C23C 2/022 (2022.08); C23C 2/0224 (2022.08); C23C 2/06 (2013.01); B23K 11/11 (2013.01); B23K 35/0255 (2013.01); B23K 35/286 (2013.01); B23K 35/3073 (2013.01); B23K 2103/04 (2018.08)] 9 Claims
OG exemplary drawing
 
1. A coated steel sheet made from a method comprising the following successive steps: coating of a steel sheet with a first coating consisting of nickel and having a thickness between 600 nm and 950 nm, the steel sheet having the following composition in weight: 0.10<C<0.40%, 1.5<Mn<3.0%, 0.7<Si<3.0%, 0.05≤ Al<1.0%, 0.75<(Si+Al)<3.0%, and on a purely optional basis, one or more elements including: Nb≤0.5%, B≤0.010%, Cr≤1.0%, Mo≤0.50%, Ni≤1.0%, Ti≤0.5%, a remainder of the composition making up of iron and inevitable impurities resulting from processing; recrystallization annealing of the coated steel sheet at a temperature between 820 to 1200° C.; and coating the steel sheet obtained in recrystallization annealing with a second coating based on zinc not comprising nickel, the coated steel sheet comprising:
a diffusion coating comprising nickel and iron formed through diffusion of nickel into a steel sheet, the diffusion coating being directly topped by a zinc based coating not comprising nickel;
the coated steel sheet having an LME crack resistance determined using 3-layer stack-up conditions of 2 cracks or less having a size above 100 μm and wherein the longest crack has a length below 450 μm.