Skip to main navigation Skip to main content
  • KIEEME

J Electr Electron Mater : Journal of Electrical and Electronic Materials

OPEN ACCESS
ABOUT
BROWSE ARTICLES
EDITORIAL POLICIES
FOR CONTRIBUTORS

Page Path

4
results for

"Tetragonality"

Keywords

Publication year

Authors

"Tetragonality"

Synthesis and Characterization of BaTiO3 Powder by Solid State Method
Yong Jin Kim, Moon Hee Choi, Hyo Soon Shin, Byeong-kwon Ju, Myoung Pyo Chun
J Electr Electron Mater 2020;33(6):483-489.   Published online November 1, 2020
DOI: https://doi.org/10.4313/JKEM.2021.33.6.10
BaTiO3 powder was synthesized by a solid-state reaction using BaCO3 and TiO2. Different calcination temperatures (800℃, 850℃, 900℃, and 950℃) were set to investigate their effects on the properties of BaTiO3 powder. The synthesized BaTiO3 phase was confirmed to be a single phase by XRD, and the tetragonality (c/a) and crystallite size were calculated. Thereafter, each calcinated BaTiO3 was sintered at five different sintering temperatures (1,100℃, 1,150℃, 1,200℃, 1,250℃, and 1,300℃), and the tetragonality, density, porosity, dielectric constant, and grain size were measured. As the calcination temperature increased, the tetragonality and crystallite size also increased, to 1.008 and 66 nm, respectively, at 950℃. Moreover, most pellets showed increased density, dielectric constant, and tetragonality as the sintering temperature increased up to 1,250℃; the same parameters slightly decreased at 1,300℃. It is noteworthy that the tetragonality of BaTiO3 at 1,250℃ exhibits a very high c/a value of 1.0084. In addition, the grain size and dielectric constant measured near the Curie temperature increased as the sintering temperature increased.
  • 9 View
  • 0 Download
Energy Materials : Precipitation Behaviors of HgTe Nanoinclusions Formed in Thermoelectric PbTe: Initial Induced Lattice Mismatch, Theoretical Calculation and Experimental Verification
Kyung Ho Kim, Tae Hyung Kwon, Su Han Park, Hyung Keun Ahn, Man Jong Lee
J Electr Electron Mater 2011;24(7):599-604.   Published online July 1, 2011
A highly strained nanostructure comprising crystallographically aligned HgTe nanoinclusions and a surrounding PbTe matrix has been synthesized using a precipitation process of supersaturated HgTe-PbTe alloys. From the early precipitation stage, HgTe nanoinclusions take disk shape, which is transformed from initial HgTe nuclei, although there is no lattice constant difference of the two end components at standard state. As a primary reason for the morphological transformation of the initial spherical HgTe nuclei to HgTe nanodisks, the induced lattice mismatch is suggested. On the condition that the HgTe nanodisks maintain perfect coherent nature with PbTe matrix, the stress-free lattice constant of constrained HgTe nanodisks has been calculated based on the defined concept of the strain-induced tetragonality, the linear elasticity and the actual measurement in HRTEM images.
  • 8 View
  • 0 Download
Effects of Nb2O5 Addition on Microstructure and Piezoelectric Characteristics of PNW-PMN-PZT Ceramics for Piezoelectric Transformer Driving PDA CCFL
Ju Hyeon Lyu, Lag Hun Hwang, Cheol Hui Kim, Dong Eon O, Eun Seong Jang, Yeong Ho Jeong, Jae Il Hong
J Electr Electron Mater 2004;17(3):289-293.   Published online March 1, 2004
  • 7 View
  • 0 Download
Microstructure and Piezoelectric Characteristics of PSN-PZT Ceramics as a Function of PNW Substitution
Ju Hyeon Lyu, Won Hui U, Dong Eon O, Seong Lim Lyu
J Electr Electron Mater 2003;16(10):892-896.   Published online October 1, 2003
  • 6 View
  • 0 Download