LAUSR

ABSTRACT Al/Cu bimetal was processed via a novel compound casting method in this paper. Interface characteristics of the Al/Cu bimetal were studied, and the generation mechanism of the interface was also discussed. The interface of the Al/Cu bimetal displayed a defect-free and uniform morphology, which was constituted by α(Al)+Al2Cu eutectic, Al2Cu, AlCu, Al4Cu9, and Si phases. The preferred crystallographic orientations of the α(Al) and Si phase growths were respectively {111} and {001}, while the textures of the Al2Cu, AlCu, Al4Cu9 phases were basically random. A bonding mechanism of the fusion and diffusion was proposed for interface formation of the Al/Cu bimetal. The interface had much higher hardness in comparison with the Al and Cu substrates, and the Al4Cu9 phase in the interface layer obtained the highest hardness, up to 9.6 GPa. The bonding strength of the Al/Cu bimetal achieved approximately 28.5 MPa. The fractographs from the fractured surface of the Al/Cu bimetal represented a brittle fracture characteristic, and the fracture mainly initiated from the α(Al)+Al2Cu eutectic.