Formation mechanism of transition zone and amorphous structure in magnetic pulse welded Al-Fe joint

Abstract

Amorphous structure and transition zone were observed in the magnetic pulse welded Al-Fe weld. Simulations and theoretical analysis were carried out to reveal the formation mechanism of the amorphous structure and transition zone. The wave morphology in the Al-Fe interface was well reproduced in simulations, and local melt was found in the weld interface. The cooling rate in the amorphous layer was much higher than that in the transition zone due to the smaller thickness of the melting layer. Materials in the amorphous layer experienced amorphization, while the materials in the transition zone experienced recrystallization. The current work indicated local melt played an important role in the magnetic pulse welding, which was different from the common perception that magnetic pulse welding was a totally solid-state welding process.