Magnetic pulse welding of Al to Mg alloys: structural–mechanical properties of the interfacial layer

Abstract

The magnetic pulse welding of Al-A1050 to Mg alloys was successfully performed, and the structural–mechanical properties of the interfacial bonding layer produced between dissimilar metals were studied. The morphology of the interface layer has a typical wavy pattern with an average thickness of 20 μm. Compositional microanalysis showed that the composition of the interfacial layer is Al–50 at-%Mg and is practically uniform, being a direct outcome of the local melting effect, intensive mixing of the melt and a rapid rate of solidification. The composition of the bonding layer corresponds to the Al supersaturated intermetallic β phase (Mg₁₇Al₁₂). The elastic modulus (and the hardness) of the interfacial layer was measured using the nanoindentation technique, and its value of 60·2±1·4 GPa is in good agreement with the value calculated from first principles in the literature (57·3 GPa) for the Mg₁₇Al₁₂ intermetallic phase.

Keywords:

• MPW
• Nanoindentation
• Elastic modulus
• Al and Mg alloys
• Interfaces

The authors wish to express their thanks to Y. Livshitz and V. Shribman from Pulsar Ltd (Yavne, Israel) for performing the MP welds, to Dr U. Admon and Dr S. R. Cohen for many fruitful discussions, to Mr C. Cotler for the preparation of the metallographic samples and to O. Kaplan for his technical assistance.