Numerical interpretation and experimental investigation of enhanced magnetoelectric effect in Ni/PZT distributed disc structured composite

The enhanced applicability of multifunctional magnetoelectric (ME) composites require them to be highly sensitive, compact and stable which has led to the development of epoxy-free self-biased ME composites. Recently proposed novel distributed disc structured (DDS) ME composite configuration led to a significant increase in ME output by a consistent increment in the number of piezoelectric discs embedded in magnetostrictive phase. This article experimentally and numerically deciphers the physics associated with the enhanced performance of DDS ME composite configurations. The enhancement in compressive prestress and the ability of DDS composites to function as multi ME composite system when operated in series combination of PZTs have been shown to be the predominant reasons attributed to the increase in ME response over the traditional disc/ring structure. The dependence of ME output of DDS composites on their orientation in applied magnetic field has been studied and the optimum placement has been identified. Finite element modeling has been used to discern the mechanical and the magnetic attributes that influence the experimentally obtained ME response with respect to connection of PZTs, angle and thickness of magnetostrictive layer. Furthermore, the ME coupling factor in various DDS configurations has been shown to be inversely dependent on the circumferential interface length.