Tensile and microbend tests of pure aluminum foils with different thicknesses

A series of systematic tensile and microbend tests was conducted on polycrystalline pure aluminum foils having the same microstructure but with different thicknesses. The thickness was changed by electropolishing. With the reduction of the foil thickness, an increase in yield strength was observed in the tensile tests, while in the microbend tests, an increase in the apparent strain-hardening modulus occurred. Numerical simulations of the microbend tests are performed using a higher-order gradient crystal plasticity theory that accounts for the effect of internal stresses due to the geometrically necessary dislocations. The trend observed in the microbend tests is reasonably reproduced in the simulations.