ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
The effect of stoichiometry, i.e. Ca/Cu ratios (CaCu3xTi4O12, x = 0.8, 0.9, 1.0, 1.1 and 1.2)on the microstructure and electrical properties was investigated. The grain sizes of CaCu3xTi4O12composition increased sharply with the increase of copper, from ~1 μm with x = 0.8 to ~50 μm with x= 1.2. The real part of dielectric permittivity changed dramatically, the pellet with x = 1.0 had thehighest dielectric permittivity ~160, 000 at 1 kHz. Furthermore, the dielectric permittivity of allpellets was impressively large values (between 10, 000 to 1, 000,000 at 100 Hz) and was nearlyconstant over a wide frequency range between 100 Hz to ~100 MHz. However, the dielectricpermittivity of CaCu3xTi4O12 composition is not consistent with the amount of copper and cellparameters and grain sizes. Impedance spectroscopy exhibited that the CaCu3xTi4O12 compositionhad two semicircle at least at high frequency (~ 107 Hz) and low frequency (〈100 Hz), respectively.The grain and grain boundary of the compositions had different impedance and relaxation behavior
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/17/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.561-565.551.pdf
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