Cured shape and snap-through of bistable twisting hybrid [0/90/metal]T laminates

This paper presents a bistable twisting CFRP-metal hybrid laminate which has an external isotropic metallic layer. Different from the pure unsymmetric CFRP laminate and the hybrid unsymmetric laminate with an inner metallic layer, the laminate presented can be transformed from one negative curvature to another negative curvature instead of from one negative curvature to another positive curvature. Their room temperature shapes can be a unique paraboloid shape, a twisted cylindrical shape, or a twisted cylindrical shape that can be snapped through to another twisted cylindrical shape. The cured shape of the hybrid laminate is studied using analytical, finite element and experimental techniques. The investigation is focused on the hybrid laminate with lay-up of [0/90/metal]T, and shows that the principal direction of cured curvature is 45°. The predicted cured shape and the snap-through loads agree well with experimental results.