Debonding Characterization of SMA/Polymer Morphing Structures

Abstract

morphing structures are expected to play an increasingly important role in aeronautic applications, among others. Shape memory alloys (SMA) are one of the most promising candidates to date. However, work remains to be done before these structures meet the stringent requirements of their successful integration in an aeronautic context. Research has shown that SMA/Polymer interface strength can be a limiting factor in active deformable structure performance. In this study, the effect on the SMA/Polymer interface strength of various surface treatments, wire geometries and resin types are evaluated. SMA wire geometry is modified through a specific combination of cold rolling and post-deformation annealing, which is capable of maintaining SMA actuating properties while achieving required cross-section area reductions. The most promising thermomechanical processing is finally proposed but results show that further work is required before SMA active elements can safely be used in an active structure.