Interface microstructure regulation and bonding performance of powder metallurgy Al/Mg bimetal with Ni interlayer

• Published in: Journal of materials science 2023-04, Vol.58 (13), p.5848-5864
• Main Authors: Tang, Zhaofeng, Yang, Lun, Wang, Tao, Wu, Lei, Ma, YunZhu, Yan, Huanyuan, Liu, Chao, Liu, Wensheng
• Format: Article
• Language: English
• Subjects: Aluminum; Bimetals; Bonding strength; Brittle fracture; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Cleavage; Crack propagation; Crystallography and Scattering Methods; Fracture mechanics; Intergranular fracture; Interlayers; Intermetallic compounds; Laminated metals; Laws, regulations and rules; Magnesium; Materials Science; Metal foils; Metal powder products; Metal powders; Metals & Corrosion; Nickel; Polymer Sciences; Powder metallurgy; Shear strength; Solid Mechanics
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-023-08362-1

Due to its excellent performance of lightweight and high strength, Al/Mg bimetal has high application value in the aerospace field. However, the poor bonding quality of the Al/Mg bimetallic interface is still an urgent problem to be solved. Therefore, this paper proposes to use Ni foil as the interlayer to control the interface structure and improve bonding strength. The results show that the Ni interlayer has a positive influence on Al/Mg interface structure regulation. The interface is composed of Al 3 Ni, Al 3 Ni 2 and Mg 2 Ni phases, and no Al–Mg brittle intermetallic compounds (IMCs) are formed. Meanwhile, the Mg 2 Ni phase is distributed as islands on the interface at 490 °C, effectively preventing crack propagation. The average shear strength of the interface reaches a maximum of 69.5 MPa. Besides, the interface fracture mechanism was deeply analyzed. The Al/Ni interface has excellent bonding performance, and the fractures occur at the Mg/Ni interface. The fracture mode from intergranular and cleavage mixed fracture at 490 °C to brittle cleavage fracture at 505 °C.