US 11,772,184 B2
Welding method for the manufacture of an assembly of at least 2 metallic substrates
Tiago Machado Amorim, Longeville les Metz (FR); Maxime Brossard, Metz (FR); Stéphanie Michaut, Remilly (FR); and Jean-Marie Helmer, Maizieres-les-Metz (FR)
Assigned to ArcelorMittal, Luxembourg (LU)
Appl. No. 17/269,356
Filed by ArcelorMittal, Luxembourg (LU)
PCT Filed Sep. 9, 2019, PCT No. PCT/IB2019/057579
§ 371(c)(1), (2) Date Feb. 18, 2021,
PCT Pub. No. WO2020/053736, PCT Pub. Date Mar. 19, 2020.
Claims priority of application No. PCT/IB2018/056998 (WO), filed on Sep. 13, 2018.
Prior Publication US 2021/0323083 A1, Oct. 21, 2021
Int. Cl. B23K 11/11 (2006.01); B32B 15/01 (2006.01); C22C 21/10 (2006.01); B23K 103/04 (2006.01); B23K 101/34 (2006.01); B23K 101/00 (2006.01)
CPC B23K 11/11 (2013.01) [B23K 11/115 (2013.01); B32B 15/012 (2013.01); C22C 21/10 (2013.01); B23K 2101/006 (2018.08); B23K 2101/34 (2018.08); B23K 2103/04 (2018.08)] 16 Claims
OG exemplary drawing
 
1. A welding method for manufacture of an assembly, the method comprising the following steps:
A. providing at least two metallic substrates including a first metallic substrate being a hardened steel part coated with:
an aluminum-based alloyed coating including zinc and silicon, and optionally magnesium, a balance being aluminum, the alloyed coating directly topped by
a native oxide layer including ZnO and optionally MgO;
B. applying a spot welding cycle, with a spot-welding machine having welding electrodes and a spot welding power source applying an inverter direct current, through the at least two metallic substrates of step A), the spot welding cycle including the following successive sub-steps:
i. applying one pulsation having a pulsation current applied through the at least two metallic substrates using welding electrodes connected to the spot welding power source to join together the at least two metallic substrates, the one pulsation having a pulsation duration, and,
ii. welding with a welding current through the at least two metallic substrates for a welding duration;
wherein a welding force during the spot welding cycle is between 50 and 350 daN, the pulsation current being different from the welding current and the pulsation duration being shorter than the welding duration, wherein there is no cooling between steps B(i) and B(ii).