Recently, a noncentrosymmetric crystal, KNaNbOF₅, has attracted attention due to its potential to present piezoelectric properties. Although α- and β-KNaNbOF₅ are similar in their stoichiometries, their structural frameworks, and their synthetic routes, the two phases exhibit very different properties. This paper presents, from first-principles calculations, comparative studies of the structura...

A high-performance flexible piezoelectric nanogenerator (PNG) is fabricated by a direct writing method, which acquires both patterned piezoelectric structure and aligned piezoelectric nanowires simultaneously. The voltage output of the as-prepared PNG is nearly 400% compared with that of the traditional spin-coated device due to the effective utilization of stress. This facile printing approach...

In this paper, a radially piezoelectric functionally graded rotating disk is investigated by the analytical solution. The variation of material properties is assumed to follow a power law along the radial direction of the disk. Two resulting fully coupled differential equations in terms of the displacement and electric potential are solved directly. Numerical results for different profiles of i...

Cement-based piezoelectric materials are widely used due to the fact that compared with common smart materials, they overcome the defects of structure-incompatibility and frequency inconsistency with a concrete structure. However, the present understanding of the mechanical behavior of cement-based piezoelectric smart materials under impact load is still limited. The dynamic characteristics und...

Abstract. The paper presents a procedure and the integrated tools for the aeroelastic analysis of an Active Twist helicopter Rotor (ATR). The active twisting of rotor blades is carried out by induced-strain actuators distributed into the structure of the blade. Active bre composites (AFC), made of piezoelectric bres actuated by interdigitated electrodes (IDE), are used to obtain anisotropic ind...

The paper presents a procedure and the integrated tools for the aeroelastic analysis of an Active Twist helicopter Rotor (ATR). The active twisting of rotor blades is carried out by induced-strain actuators distributed into the structure of the blade. Active bre composites (AFC), made of piezoelectric bres actuated by interdigitated electrodes (IDE), are used to obtain anisotropic induced-strai...

Following the first demonstration of fiber-based piezoelectric element that can be interfaced with external circuits in both transmitter and receiver configurations, we continue to explore the refinement of the fabrication process on novel and high performance structures: fibers with circular and rectangular cross sections have been fabricated to control the acoustic wavefronts. Fibers containi...

The existence of enormous strain fields in self-assembled quantum dots has led to the expectation of dramatic effects of piezoelectricity. However, only linear piezoelectric tensors were used in all previous calculations. We calculate the piezoelectric properties of self-assembled quantum dots using the linear and quadratic piezoelectric tensors derived from first-principles density functional ...

A frequency domain system modelling technique is developed for mechanical systems. The technique is derived from Tellegen's Theorem for electrical networks and is applied to discrete mechanical systems. The elements are modelled in terms of their mechanical impedances. A global system model is assembled from the constitutive impedances. The global system model is used to determine the model exa...

Piezoelectrics have widespread use in today's sensor and actuator technologies. However, most commercially available piezoelectric materials, e.g., Pb [Zr(x)Ti(1-x)] O(3) (PZT), are comprised of more than 60 weight percent lead (Pb). Due to its harmful effects, there is a strong impetus to identify new lead-free replacement materials with comparable properties to those of PZT. This review highl...