Recent developments on Smart Composites with embedded SMA wires and FBG sensors(International Workshop on Smart Materials and Structural Systems, W03 Jointly organized by Material & Processing Division, Material & Mechanics Division, Dynamics & Control Division and Space Engineering Division.)

Abstract

Shape memory alloy wires are nowadays available in small diameters, allowing their direct integration into polymer composite materials without altering the integrity of the structure. These hybrid materials offer the potential to adapt their shape, thermal or vibration response, when they are heated above the transformation temperature of the SMA. This requires to master both their design and processing to reliably produce the desired level of activation. Additionally, strain and temperature sensing should be integrated as well in the composite, to allow for a closed-loop control. This is achieved by embedding Fiber Bragg Grating optical fibers. Recent results will be reviewed, with particular emphasis on the processing issues including the choice of materials and of a manufacturing route for the embedment of pre-strained wires, the development of internal stresses in the host material during post-cure and activation, and the evaluation of the interfacial strength required to sustain the activation induced stresses. The use of coupled FBG sensors to simultaneously measure temperature and strain will be presented, with results from on-going research.