Modelling of springback in creep forming thick aluminum sheets

Integrated numerical techniques have been developed to predict springback in creep forming thick aluminum sheet components using physically-based unified creep constitutive equations, which model the primary hardening, ageing, creep constrained damage and their effects on creep deformation of an aluminum alloy. Springback effects have been studied for two aluminum shapes. One is a single curvature cylindrical component and the other is a doubly curved spherical component. Stress relaxation and creep deformation of the aluminum sheet under different forming conditions are studied. The effects of forming processes and the thickness of the material sheet on springback of formed parts are investigated. The amount of springback on forming doubly curved and single curvature sheet components is predicted and compared for different forming conditions.