With an increasing use of adhesively bonded joints in the industry, there is a correspondingly growing need for the inspection of adhered joints. It is necessary to detect defects in the adhesively bonded materials such as voids inclusions, chemical miscure of the adhesive, or delaminations of the bonded layers. In order to use an ultrasonic technique to detect these defects, a thorough underst...

In this work, lateral-field-excitation (LFE) piezoelectric sensors based on polarity inversion layer are designed and fabricated, then frequency stabilities sensitivities electric property changes of liquids tested. Because the can suppress spurious modes, LFE devices with a obviously better than that no layer. On liquid conductivity permittivity, 2.4 times 2.1 higher layer, respectively. The l...

energy harvesting from surrounding environment has been attractive for many researchers in recent years. therefore, developing appropriate test apparatus to study energy harvesting mechanisms and their performance is of paramount importance. due to their electromechanical characteristics, piezoelectric materials are used for harvesting energy from environmental vibrations. for optimum utilizati...

In this paper, we present mathematical analyses to consider the effect of material properties on the sensitivity of the Microelectromechanical systems (MEMS) piezoelectric hydrophone and improve the sensitivity by choosing the proper material. The selected structure in the present paper is a piezoelectric hydrophone able to work at low frequencies. The piezoelectric hydrophones are widely used ...

In this paper, a novel aluminum nitride (AlN) resonant pressure sensor with piezoelectric-excitation and piezoelectric-detection is presented. The key structure of resonator an AlN flexible beam. Parallel electrodes are designed on the beam to excite resonance in-plane. All layers grown silicon-on-insulator (SOI) wafer by deposition process. Anchor islands fabricated in top silicon layer SOI. o...

The behaviour of a piezoelectric actuator is strongly affected by the bonding condition along the interface between the actuator and the host structure. The current paper represents an analytical study of the static effect of the mechanical and geometrical properties of the adhesive layer on the coupled electromechanical behaviour of a thin piezoceramic actuator bonded to an elastic medium. An ...

The behaviour of a piezoelectric sensor is strongly affected by the bonding condition along the interface between the sensor and the host structure. The current paper represents an analytical study of the static effect of the mechanical and geometrical properties of the adhesive layer on the coupled electromechanical behaviour of a thin piezoceramic sensor bonded to an elastic medium. A sensor ...

Pre-stressed piezoelectric laminates, consisting of one or more metal layers and a piezoelectric material bonded together with an adhesive, have been widely studied over the past few years, both numerically and experimentally. Most of the current research has concentrated on the effect of the metal layers, types and geometry, along with variations in the active layer of the laminate. Historical...

We demonstrate the fabrication of a graphene/ZnO nanorod (NR) hybrid structure by mechanical exfoliation of ZnO NRs grown on a graphite substrate. We confirmed the existence of graphene sheets on the hybrid structure by analyzing the Raman spectra and current-voltage (I-V) characteristics. The Raman spectra of the exfoliated graphene/ZnO NR hybrid structure show G and 2D band peaks that are shi...