In recent years shape memory effect in polymer systems has drawn great attention for its potential applications for MEMS and medical devices. In this paper, the visco-elastic and plastic behavior and strain recovery characteristics of a thermoplastic have been studied extensively. Creep deformation by compression was performed under load or displacement control mode, and under monotonic or cyclic loading. The strain recovery ratio of the shape memory polymer is found to be strongly affected by the deformation temperature, isothermal holding temperature and time, amount of forward strain and relaxation time, and the number of cycles of strain/recovery. The creep behavior of the material is modeled.

Volume Subject Area:
Materials
Topics:
Mechanical behavior, Shape memory polymers, Creep, Temperature, Compression, Cycles, Deformation, Displacement, Medical devices, Microelectromechanical systems, Polymers, Relaxation (Physics), Shape memory effects, Stress
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