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The present study is a baseline assessment of the environmental durability of current state-of-the-art, fabric-reinforced shape memory materials being considered for morphing applications. Tensile dog-bone-shaped specimens are cut along three different directions, namely, along 0°, perpendicular (90°), and at 45° to the orientation of the fabric. The shape memory properties and elastomeric response before and after relevant environmental exposure to water at 49°C for 4 days, in lube oil at room temperature and at 49°C for 24 hours, and after exposure to Xenon Arc (63°C, 18 minutes water and light/102 minutes light only) and spectral intensity of 0.3 to 0.4 watts/m2 for 125 cycles (250 hours exposure time) are measured. Weight loss of the as-received and conditioned specimens is monitored while the dog-bone-shaped specimens are subjected to recovery following fixation. Parameters being investigated include stored strain, recovery stress, shape fixity, shape recovery, and modulus in the glassy and rubbery state.Copyright © 2009 by ASME |