PRELIMINARY INVESTIGATIONS OF THE LOW-VELOCITY IMPACT RESPONSE OF A SMART TRIMORPH PLATE FOR ACTIVE DAMAGE MITIGATION

The elastoplastic impact response of a trimorph plate subjected to low-velocity large mass impact has been investigated using analytical models. In formulating the impact model, the displacement of the impactor, vibration of the plate and local contact mechanics were accounted for. The vibration of the trimorph plate was modelled using the classical laminate plate theory, while the local contact mechanics was modelled using a Meyer-type compliance model that accounts for post-yield effects in the loading and unloading stages of the impact. The impact model is a set of coupled nonlinear differential equations and was solved using the NDSolve function in Mathematica™. Both the modelling and solution approach were validated using a benchmark case study. Investigations were carried out for an Al/PVDF/PZT trimorph plate configuration. Contrary to the general position in the literature that the response of a large mass impact is insensitive to the compliance model used to estimate the impact force (1), the simulations of the present impact model show that the indentation history was sensitive to the compliance model used. Also, the elastoplastic compliance model predicted a permanent indentation which the elastic compliance model cannot estimate. Therefore, the use of elastoplastic compliance models in large mass impact analysis is imperative. Finally, the application of a smart trimorph plate with piezoelectric actuator layer for active mitigation of impact damage was discussed.