Anisotropic Deformation Behavior and Forming Limit of Hot-Rolled Al/Mg/Al Three-Layered Composite Sheets

The anisotropic deformation behavior and forming limit of hot-rolled Al/Mg/Al three-layered composite sheets have been investigated in detail. Uniaxial tensile tests were conducted on composite sheets at 0°, 45°, and 90° to the rolling direction. The results show that the properties of the hot-rolled 5052/AZ31/5052 three-layered composite sheet with fine grain distribution and diffusion layer of 18.71 μm were anisotropic and showed temperature dependence. The 0° direction showed the highest n value and the 90° direction the lowest. The highest Lankford parameter was found in the 45° direction, with the maximum r¯ value and minimum absolute value of Δ r at 230°C. Moreover, hemispherical punch tests revealed that the composite sheet exhibited better formability at 230°C than 170°C, especially in the biaxial stress state. In the equibiaxial tensile stress state, significant anisotropy of the thickness distribution and different fracture appearance were also observed.