Cyclic Electro-Mechanical Modelling of Uniaxially Stretched PVDF
20 Oct 2021-Transactions of The Indian Institute of Metals (Springer India)-Vol. 74, Iss: 10, pp 2511-2520
TL;DR: In this article, the authors used two approaches to model cyclic stress with the number of cycles and the effect of cyclic loading on the material, in terms of entropy generation for mechanical and electrical response, is considered for modelling and this approach is adopted to model the PVDF response when subjected to cyclic load.
Abstract: Polyvinylidene fluoride (PVDF) is a piezopolymer, and it has numerous applications as sensors and actuators. Uniaxially stretched PVDF subjected to cyclic stresses finds usage in different applications. Characterising the cyclic response of PVDF through appropriate models is important. In this study, we used two approaches to model cyclic stress with the number of cycles. In the first approach, the evolution equations are used and adopted to model the variation of the cyclic mechanical response of PVDF to track the cyclic response at each time step. In the second approach, the effect of cyclic loading on the material, in terms of entropy generation for mechanical and electrical response, is considered for modelling and this approach is adopted to model the PVDF response when subjected to cyclic loading. The mean stress and voltage variation with the number of cycles are predicted.
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