Joints formation and bonding mechanism of ultrasonic welded multi-strand single core copper cables with copper terminals

Abstract

• Metallurgical bonding of multi-strand single core copper cables with copper terminals was achieved by ultrasonic welding technology. • Formation of bonding interfaces involved plastic deformation, dynamic recrystallization, and dynamic recovery. • Fine equiaxed grains at the bonding interfaces were beneficial to increase the strength of the joints. The metallurgical bonding of multi-strand single core copper cables with copper terminals was achieved by ultrasonic welding technology. The joint forming process and bonding mechanism that involved plastic deformation, dynamic recrystallization and dynamic recovery were clarified. The necklace-like fine grains structures observed in the central areas of the bonding interfaces would significantly improve the T -peel strength of the joints.