The morphing properties of a smart fiber metal laminate

Abstract

This article investigates the activation characteristics of a novel fiber-metal laminate (FML) based on a nickel-titanium (Ni-Ti) shape memory alloy. Initial attention focuses on manufacturing this smart FML in which a woven glass fiber reinforced epoxy material is sandwiched between two shape memory alloy (SMA) outer skins. Activation tests on cantilever beams using a hot air gun have shown that the FMLs exhibits a distinct actuation capability in which beam rotations of up to 11° were recorded. An examination of the edges of polished samples indicated that no damage was incurred by the FML during the activation process. The functionality of the FMLs was enhanced through the introduction of embedded electrical resistance wires located between the composite and metal plies. Here, the embedded electrical wires were heated by passing an electric current through them, thereby activating the SMA plies in a more effective and controllable manner. As before, significant beam tip rotations were recorded in the FMLs in a relatively short time period. Finally, polymer-based optical fiber (POF) and fiber-bragg grating (FBG) sensors were introduced into the FMLs in order to monitor their deflection during the activation process. The results of these tests showed that such sensing elements can be successfully employed to monitor the actuation response of these layered laminates. © 2008 Society of Plastics Engineers.