Forming Limit and Interface Diffusion Behavior of 5052/AZ31/5052 Tri-layer Clad Sheet

Abstract:

5052/AZ31/5052 tri-layer clad sheet is a new material with energy saving and consumption reduction. It is of vital significance to study its formibility for its wide applications in industrial field. The forming limit curves of 5052Al/AZ31Mg/5052Al tri-layer clad sheet at 170℃ and 230℃ were obtained respectively by using hemispherical punch. Fracture morphology at limit position and the interface diffusion behavior during bulging process were studied. The results showed that: 5052Al/AZ31Mg/5052Al tri-layer clad sheet has a superior formability at 230℃; the bulging process promoted magnesium and aluminum elements near the bond interface distributed homogeneously and had little effect on the thickness of diffusion layer; the defects were eliminated and the mechanical occlusion areas of bond interface were increased by the bulging process, which is beneficial to improve the bond strength of the interface.

Key words:clad sheet; forming limit curve;fracture;bond interface;diffusion