Bending actuation characteristics of shape memory composite with SMA and SMP

A shape memory composite (SMC) belt with a TiNi-shape memory alloy (SMA) wire fiber and a polyurethane-shape memory polymer (SMP) sheet matrix is fabricated. The bending actuation characteristics of the belt are investigated by the thermomechanical tests. The results obtained are summarized as follows. (1) Residual deflection close to the maximum deflection is obtained by cooling under constant maximum deflection. The residual deflection disappears by heating under no load. Both the rate of shape fixity and the rate of shape recovery are close to 100%. (2) Recovery force appears by heating under constant residual deflection. The recovery force is 93-94% of the maximum force. The development of high functionality of SMC elements is expected by various combinations of SMAs and SMPs.