Stress-Strain Behavior of Thermoplastic Polyurethane
نویسندگان
چکیده
The large strain nonlinear stress-strain behavior of thermoplastic polyurethanes (TPUs) exhibits strong hysteresis, rate dependence and softening. Thermoplastic polyurethanes are copolymers composed of hard and soft segments. The hard and soft segments phase separate to form a microstructure of hard and soft domains typically on a length scale of a few tens of nanometers. Studies have revealed this domain structure to evolve with deformation; this evolution is thought to be the primary source of hysteresis and cyclic softening. In this paper, experiments and a constitutive model capturing the major features of the stress-strain behavior of TPUs, including nonlinear hyperelastic behavior, time dependence, hysteresis, and softening, are presented. The model is based
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