Abstract:The deformation mechanism will be more intricate by the size effect when the characteristic size of metal parts is reduced to a micro scale. In this paper, the aging Inconel 718 foil with thickness of 0.1mm was selected as the study subject and tested for its mechanical properties. Based on the data mechanical test, the anisotropy, elongation, yield strength and maximum tensile strength of aging Inconel 718 foils were explored under different tensile direction and uniform strain rate. And the predicted model of anisotropy and yield strength and the hardening model for considering the strain and strain rate are established. The research results show that the aging Inconel 718 foils have conspicuous anisotropy. The tensile direction of 45° is an extreme point for the anisotropy, elongation, yield strength and maximum tensile strength. The elongation and anisotropy firstly increase and then decrease with the increase of angle between tensile direction and rolling direction. But the change rule of yield strength and maximum tensile strength is opposite to elongation and anisotropy. In order to accurately predict the anisotropy and yield strength, two different sets of material parameters are needed due to the size effect. When the strain rate is higher than 0.1 s-1, the material yield strength shows obvious sensitivity for strain rate. In this moment, the above hardening model is not applicable.