US 12,479,040 B2
Resistance-welded assemblies and resistance welding methods
Zhenke Teng, Troy, MI (US); Pei-Chung Wang, Troy, MI (US); and Jason M Brown, Goodrich, MI (US)
Assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed by GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed on Jan. 14, 2022, as Appl. No. 17/648,040.
Prior Publication US 2023/0226636 A1, Jul. 20, 2023
Int. Cl. B23K 11/11 (2006.01); B23K 11/00 (2006.01); B23K 11/18 (2006.01); F16B 5/08 (2006.01)
CPC B23K 11/115 (2013.01) [B23K 11/0026 (2013.01); B23K 11/185 (2013.01); F16B 5/08 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for resistance welding, the method comprising:
providing a workpiece stack-up including a first workpiece, a second workpiece, and an interface material located between the first workpiece and the second workpiece, wherein each workpiece has a thickness of less than about 3 mm and each workpiece is aluminum or an aluminum alloy, wherein the interface material has an initial thickness and wherein the interface material is a polymeric material, has a flexural modulus of from 1.5×105 to 5×105 psi, has a flexural strength of from 5,000 to 15,000 psi, has a resistivity of at least 10 μΩ·cm, and has a melting point of about 660° C. or less;
bringing a first welding electrode into contact with the first workpiece at an initial contact area and bringing a second welding electrode into contact with the second workpiece;
compressing the workpiece stack-up with the first welding electrode and the second welding electrode to squeeze a squeezed portion of the interface material to a reduced thickness less than the initial thickness, wherein, after compressing the workpiece stack-up, the first welding electrode contacts the first workpiece at an operating contact area between the first welding electrode and the first workpiece that is greater than the initial contact area;
passing an electrical current between the first welding electrode and the second welding electrode to form a molten weld pool within the first workpiece and the second workpiece; and
ceasing the passing of the electrical current between the first welding electrode and the second welding electrode to allow the molten weld pool to solidify into a weld nugget that forms all or part of a weld joint between the first workpiece and the second workpiece.