US 12,460,282 B2
Crack-containing hot-stamped coated steel part with excellent spot-weldability and excellent painting adhesion
Clément Philippot, Ennery (FR); Doriane Serra, Talange (FR); Hubert Salmon Legagneur, Paris (FR); and David Dussaussois, Homecourt (FR)
Assigned to ArcelorMittal, Luxembourg (LU)
Appl. No. 18/757,440
Filed by ArcelorMittal, Luxembourg (LU)
PCT Filed Feb. 9, 2024, PCT No. PCT/IB2024/051221
§ 371(c)(1), (2) Date Jun. 27, 2024,
PCT Pub. No. WO2024/134632, PCT Pub. Date Jun. 27, 2024.
Claims priority of application No. PCT/IB2023/056827 (WO), filed on Jun. 30, 2023.
Prior Publication US 2025/0114837 A1, Apr. 10, 2025
This patent is subject to a terminal disclaimer.
Int. Cl. C22C 38/04 (2006.01); B21D 22/02 (2006.01); C21D 6/00 (2006.01); C21D 8/02 (2006.01); C22C 21/02 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/14 (2006.01); C23C 2/12 (2006.01)
CPC C22C 38/04 (2013.01) [B21D 22/022 (2013.01); C21D 6/005 (2013.01); C21D 8/0205 (2013.01); C21D 8/0226 (2013.01); C21D 8/0273 (2013.01); C21D 8/0278 (2013.01); C22C 21/02 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/14 (2013.01); C23C 2/12 (2013.01); C21D 2211/001 (2013.01); C21D 2211/002 (2013.01); C21D 2211/005 (2013.01); C21D 2211/008 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A hot-stamped coated steel part comprising a steel substrate and an aluminum alloy coating on at least one face of the steel substrate, the coating comprising, proceeding from steel substrate outwards, an interdiffusion layer and an outer layer, wherein a total thickness of the coating ecoating and a thickness of the interdiffusion layer eIDL satisfy the following condition:

OG Complex Work Unit Math
eIDL designating the thickness of the interdiffusion layer in μm, and ecoating designating the total thickness of the coating in μm,
and wherein, the hot-stamped coated steel part comprises an undeformed portion having a thickness ePflat from 0.6 mm to 3.5 mm, and at least one deformed portion, a lineic density of cracks dC in the coating in the undeformed portion is lower than or equal to 4*dCmin(ePflat) and is higher than or equal to a minimum lineic density of cracks dCmin(ePflat) defined as:

OG Complex Work Unit Math
wherein dC and dCmin(ePflat) are expressed in numbers of cracks per mm, and epflat designates the thickness of the undeformed portion in mm.