Bond strength and bonding interface of Ni/Al dissimilar joint by spot forge-welding

Nickel and aluminum lap joining of a 1-mm-thick sheet each was performed using the spot forge-welding method. Direct joining was conducted with an 8-mm-diameter punch in a bonding time of 77 ms. The tensile shear load of the joint reached 5.3 kN, and the 10(7) fatigue limit in cyclic tension was 1.3 kN. In each of the fracture forms, base metal fracture on the aluminum side was realized. The reaction layer at the bonding interface had a thickness of 400-500 nm and was divided into two layers. This result is expected to be useful in next-generation spot solid-phase bonding methods, for high throughput production of electrical parts and electrodes that realize high-strength dissimilar material bonding. (C) 2021 Elsevier B.V. All rights reserved.