In order to improve the output capacity of a piezoelectric pump when transferring gas, this paper presents a compact resonant piezoelectric diaphragm pump (hereinafter referred to as the piezoelectric diaphragm pump), which is driven by a rectangular piezoelectric vibrator. The compact structure can effectively release the vibrating constraints of the vibrator, and enlarge its center output dis...

The increasing development of smart materials, such as piezoelectric and shape memory alloys, has opened new opportunities for improving repair techniques. Particularly, active repairs, based on the converse piezoelectric effect, can increase the life of a structure by reducing the crack opening. A deep characterization of the electromechanical behavior of delaminated composite structures, acti...

Enhancing the output power of a nanogenerator is essential in applications as a sustainable power source for wireless sensors and microelectronics. We report here a novel approach that greatly enhances piezoelectric power generation by introducing a p-type polymer layer on a piezoelectric semiconducting thin film. Holes at the film surface greatly reduce the piezoelectric potential screening ef...

Dynamic fracture mechanics of layered materials has been gaining lots of attentions among the researchers where the layered materials are extensively used in various products and devices to improve structural performance such as strength and durability. The influence of the crack moving speed on the the stress intensity factors was a popular subject in classical elastodynamics. Among the models...

Electric potential produced in deformed piezoelectric nanostructures is of significance for both fundamental study and practical applications. To reveal the piezoelectric property of ZnO nanohelices, the piezoelectric potential in single-crystal nanohelices was simulated by finite element method calculations. For a nanohelix with a length of 1200 nm, a mean coil radius of 150 nm, five active co...

Piezoelectric nanopositioning actuators are widely employed in many applications, including the hard disk drives [1–3], gyroscopes [4] and the scanning probe microscopes [5]. Besides the precise position control, high-bandwidth tracking control is crucial for the applications of piezoelectric actuators, since, for example, it will allow hard disk drives to meet the demand for higher data storag...

A piezoelectric dispenser has been fabricated based on the idea of a piezoelectric-metal-cavity (PMC) actuator. The PMC actuator consists of a metal ring sandwiched between two identical piezoelectric unimorphs. The radial contraction of the piezoelectric ceramic is converted into a flextensional motion of the unimorph, causing a large flexural displacement in the center part of the actuator. W...

This paper investigates application of piezoelectric ceramics mounted on surface of mould to monitor flow front and curing phases of resin in Resin Transfer Moulding (RTM) process. The piezoelectric ceramic is used for both generating ultrasound and measuring energy of echoed ultrasonic wave at the interface of mould and resin. One of the advantages of this method is that the piezoelectric cera...

Flexoelectricity is an electromechanical effect coupling polarization to strain gradients. It fundamentally differs from piezoelectricity because of its size-dependence and symmetry. Flexoelectricity is generally perceived as a small effect noticeable only at the nanoscale. Since ferroelectric ceramics have a particularly high flexoelectric coefficient, however, it may play a significant role a...

Piezoelectric sensing is of increasing interest for high-temperature applications in aerospace, automotive, power plants and material processing due to its low cost, compact sensor size and simple signal conditioning, in comparison with other high-temperature sensing techniques. This paper presented an overview of high-temperature piezoelectric sensing techniques. Firstly, different types of hi...