Enhancement of the inverse method enabling the material parameter identification for piezoceramics

Abstract

We present a mathematical Inverse Method providing reliable material parameters of piezoceramic materials. Thereby, a systematic matching of finite element simulations to measurements yields the complete set of material parameters. Contrary to our previous research where we utilized both, frequency resolved electrical impedances and spatially resolved surface velocities, only the impedance curves serve as input quantity of the enhanced Inverse Method. Within this method, two block shaped piezoceramics of equal geometric dimensions but different directions of electrical polarization are investigated. For the piezoceramic material PIC255, the identified material parameters exhibit to some extent deviations from the manufacturer's parameters of more than 20 %. For verification purposes, we perform finite element simulations of a discoidal piezoceramic material which was not considered for the Inverse Method. Comparisons with measurements demonstrate that the identified parameters can be used to precisely predict the behavior of piezoceramic materials.

Determination of temperature dependences of material constants for lead-free (Na0.5K0.5)NbO3–Ba2NaNb5O15 piezoceramics by inverse method

“…Furthermore, all the piezoelectric constants e xy of NKN-1.5BNN are higher than those of NKN-Mn. In particular, the piezoelectric shear mode e 15 of NKN-1.5BNN was comparable to that (11.9 26) ) of the PZT-based ceramic PIC255 (PI Ceramic). Upon comparing the tensors of elastic stiffness constants, only the elastic stiffness constant c E 44 of NKN-1.5BNN was found to be comparable to that of NKN-Mn.…”

Consistent approach to describe and evaluate uncertainty in vibration attenuation using resonant piezoelectric shunting and tuned mass dampers

“…As for the resonant shunt, the maximum deviation of the piezoelectric coefficient d 31 varies up to ±10% based on [19]. The capacitance C p is affected by the transducer's geometry and the bonding to the beam.…”

Determination of frequency and temperature dependent mechanical material properties by means of an Inverse Method

“…The variable material parameters are the real part of the elasticity modulus , the damping factor , and the Poisson's ratio . Typically, the complex Young's modulus is given by j (2) and the damping factor or loss factor tan is defined by the quotient between imaginary and real part :…”

“…Within the second step, the transfer function around the resonances is considered for the optimization based on an iteratively regularized Gauss-Newton method (see e.g., [2,9,15]). This algorithm minimizes the difference between the measured and the simulated transfer function in the least square sense.…”

“…Especially for sensors and actuators, an exact knowledge of mechanical as well as electrical quantities yields reliable simulations and ensures the functionality of a device. For the identification of the material parameters of piezoceramic transducers, we already introduced a so-called Inverse Method [1,2]. Based on this method, the present contribution deals with a similar procedure to investigate the dynamic as well as thermal dependencies of mechanical material properties, namely elasticity modulus, Poisson's ratio, and a damping factor.…”