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 degrees, 45 degrees, and 90 degrees 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 18.71m were anisotropic and showed temperature dependence. The 0 degrees direction showed the highest n value and the 90 degrees direction the lowest. The highest Lankford parameter was found in the 45 degrees direction, with the maximum r value and minimum absolute value of r at 230 degrees C. Moreover, hemispherical punch tests revealed that the composite sheet exhibited better formability at 230 degrees C than 170 degrees 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.