2018 Marine Information Forum – Session 32

Date:2018-10-12Author:Source:College of Underwater Acoustic EngineeringHits:30

2018 Marine Information Forum – Session 32

Presentation title: “Transverse Resonance Orthogonal Beam (TROB) Single Crystal Underwater Transducers

Presenter: Dr. Shuangjie Zhang

Time: 9:00-10:00 am, Oct. 15, 2018

Location: Conference Room 315 of the Underwater Acoustic Engineering Building

Short Bio of the presenter:

Shuangjie Zhang received his B.Eng and Ph.D. degrees in mechanical engineering from National University of Singapore in 2010 and 2018, respectively. From 2010, he has been with Microfine Materials Technologies P/L (Singapore), and is currently the product manager of the company, responsible for development of piezoelectric underwater devices and processing of piezoelectric single crystals. His research interests include design and analysis of piezoelectric underwater sensors and transducers, as well as ferroelectric single crystal property characterization.

Abstract of the presentation:

Relaxor-based ferroelectric single crystals such as Pb(Zn1/3Nb2/3)O3-PbTiO3 (PZN-PT), Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) and Pb(In1/2Nb1/2)O3-Pb(Zn1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) exhibit ultrahigh piezoelectric strain coefficients (d33 >1400 pC/N; –d32 >1600 pC/N) and electromechanical coupling factors (k33  k32 >0.9). They are candidate active materials for high-performance broadband medical, industrial and underwater transducers involving transmission and reception of large amounts of signals and information. In this research, using the excellent transverse piezoelectric properties and extremely high Poisson’s ratio of PZN-PT single crystals, a new drive mode for broadband underwater sound generation, called the Transverse Resonance Orthogonal Beam mode, has been devised. Unlike the conventional modes in which the resonating direction and the acoustic beam direction are identical, in the TROB mode, the active material is set in resonance in half-wavelength mode in one transverse direction, and the acoustic beam is generated in a direction orthogonal to the resonating transverse direction.

Since the output generated by the TROB mode is in-phase with and comparable to those of the conventional modes, the new TROB mode can be used to broaden the bandwidth of the projector.