Adaptive post-buckling response of carbon fibre composite plates employing SMA actuators

Abstract Restoration forces, associated with embedded activated pre-strained SMA wires, have successfully been employed to enhance the post-buckling behaviour of laminated plate structures while under the influence of a uniaxial load. The results of which will be presented. The manufacturing methodology of the hybrid SMA-carbon-epoxy plates is outlined. Optical micrographs illustrate the effect of embedding diametrical inclusions within a host composite. Thermal and structural finite-element analysis have been employed to predict the non-uniform temperature profile within the laminates and to provide insight to the SMA-hybrid structure adaptive response. It is shown that by utilizing the considerable control authority generated, even for a small actuator volume fraction, the out-of-plane displacement of the post-buckled laminates can be significantly reduced. Such displacement alleviation allows for the load redistribution away from the plate's unloaded edges i.e. there is a tendency for the plate to conform to the optimal flat configuration beyond its critical buckling load. However, the stability of the adaptive response is very much dependent upon the laminate stacking sequence. It is envisaged that the range of operational performance for such an adaptive hybrid structure may be extended over conventional materials and structures.