This article outlines new low-cost hardware set-ups as viable substitutes for conventionally employed cost-intensive impedance analyzers/LCR meters for implementation of the electro-mechanical impedance (EMI) technique for SHM/NDE. The proposed solutions warrant basic low-cost equipment, such as function generator and digital multimeter, which are commonly available in most laboratories. Unlike the case of impedance analyzers/LCR meters, only the absolute admittance (i.e., magnitude) is measured. A simple computational approach is outlined for effective utilization of the absolute admittance function for SHM after filtering the passive component. Comparison of results with LCR measurements shows that the measurement accuracy of the proposed set-up is fairly good, repeatability excellent, and the damage sensitivity comparable to that of the cost-intensive conventional hardware. The proposed adaptation is, therefore a suitable candidate for the widespread industrial applications of the EMI technique.

The lead-free 0.5((Ba 0.7 Ca 0.3)TiO 3)-0.5(Ba(Zr 0.2 Ti 0.8))O 3 (BCZT) piezoceramics were synthesized using sol-gel method. The Rietveld analysis of X-ray diffraction (XRD) data and differential scanning calorimetry (DSC) studies of as-synthesized BCZT powder suggests the coexistence of ferroelectric orthorhombic (O) and tetragonal (T) phases at room temperature (RT). The value of curie temperature (T T-C) as depicted from DSC and dielectric studies was found to be ≈ 110 C. The BCZT ceramic particles were dispersed in the polyvinylidene fluoride (PVDF) matrix, an electroactive polymer with great ferro/piezoelectric response in its distinct β and γ phases, to form ferroelectric ceramic-polymer composites for their applications in flexible energy storage capacitors. The present work reports the Fourier-transform infrared spectroscopy (FTIR), XRD, dielectric, ferroelectric, and energy density properties of PVDF/BCZT composite films having different wt% of BCZT content fabricated by the solution-cast technique. The FTIR and XRD studies depict the γ-PVDF and pure BCZT phases in composite films. The dielectric studies estimated the relative permittivity (ε r) of a composite film with 50 wt% of BCZT content to be ≈ 31 (at 120 Hz) which was about three times as compared with that of pure PVDF. The dielectric loss (tan δ) was maximum ≈ 0.15 (at 120 Hz) for 50 wt % BCZT composition. The ferroelectric studies and energy storage calculations showed that the value of remnant polarization (P r), coercive field (E c) and energy storage density (W) attain the maximum value of 0.63 μC/cm 2 , 35.22 kV/cm, and 70.46 mJ/cm 3 , respectively for the film sample having 40 wt% BCZT content. The maximum energy storage efficiency, η (%) is calculated to be ≈ 60 for 50 wt% BCZT composition. The results indicated that the incorporation of BCZT particles

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