About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
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Symposium
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Mesoscale Phenomena in Functional Polycrystals and Their Nanostructures
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Presentation Title |
Characterization of Phase and Domain Switching in Sn-doped BCZT Piezoceramics with Large Electromechanical Strains |
Author(s) |
Abhijit Pramanick, Laurent Daniel, Sarangi Venkateshwarlu, Valentin Segouin, Yang Ren |
On-Site Speaker (Planned) |
Laurent Daniel |
Abstract Scope |
Piezoceramics are desired for various applications, such as sensors and actuators, biomedical instruments and energy harvesting. In order to obtain large electromechanical strains, piezoceramic compositions are often designed to favor a coexistence of multiple ferroelectric phases. For such compositions, the significance of microscopic phenomena viz. domain switching and phase transitions towards macroscopic materials response are not clearly understood. In this work, we use a combination of strain measurements from digital image correlation (DIC), in situ synchrotron X-ray diffraction and multiscale micromechanical modeling to self-consistently describe the electric-field-induced microscopic mechanisms in a polycrystalline Pb-free piezoceramic, Sn-doped (Ba,Ca)(Zr,Ti)O3 (BCZT), which was shown to exhibit a large electrostrain coefficient of d33* ~ 600 pm/V under low electric fields (< 1 kV/mm). We reveal that large electrostrains in Sn-doped BCZT piezoceramics can be attributed to a unique phenomenon, wherein domain switching in the tetragonal phase is aided by a reversible tetragonal-orthorhombic-tetragonal (T-O-T) phase transformation. |