Ferroelectric relaxation dependence of poly(vinylidene fluoride-co-trifluoroethylene) on frequency and temperature after grafting with poly(methyl methacrylate)

By monitoring the D–E curves of P(VDF-TrFE-CTFE)-g-PMMAs at different frequency and temperature, the dependence of the ferroelectric relaxation of grafted copolymers onto testing conditions and composition has been finely illustrated.

Monotonic Testing and Tension-Tension Fatigue Testing of Free-standing Al Microtensile Beams

ABSTRACTFree-standing Al thin films were loaded statically and dynamically through the use of a custom-built microtensile system. The system is capable of performing monotonic loading/unloading up to 50 μm/s (10-1/s) and tension-tension fatigue experiments at 100 Hz on 600 μm long, 100 μm wide, and 1 μm thick free-standing Al microtensile beams. Monotonic loading/unloading and stress relaxation experiments have been performed. The microtensile beams show plasticity as well as a relaxation dependence on strain rate and stress level. Displacement controlled tension-tension fatigue experiments have also been performed. A trend of decreasing cycles to failure with increasing displacement amplitude and increasing mean displacement has been noted but requires further experimental exploration.