TY  - JOUR
T1  - Modelling Power Law Dependencies of Frequency Dependent AC Conductivity and Permittivity of Conductor-Relaxor Composites
A1  - Bowen,C.R.
A1  - Dent,A.C.E.
A1  - Almond,D.P.
A1  - Comyn,T.P.
Y1  - 2008///
KW  - Composite
KW  - Dielectric
KW  - PMN-PT
KW  - Porous
KW  - Power law
KW  - Relaxor
SP  - 166
EP  - 175
JF  - Ferroelectrics
JA  - Ferroelectrics
VL  - 370
IS  - 1
PB  - Taylor & Francis
N2  - Porous lead magnesium niobate-lead titanate (PMN-PT 90:10) relaxors were impregnated with water to provide a model conductor-insulator mixture, to study their power law frequency dependency of ac conductivity, permittivity and phase angle. Relaxor materials with a range of open porosity filled with water created composites with conductor volume fractions ranging from 8.2% to 22.2%. The use of a high relative permittivity PMN-PT (~8000) enabled the power law dispersion to be observed at relatively low frequencies (~2 kHz). Good agreement was obtained between experimental data and predicted results based on a logarithmic mixing rule with a strong correlation between the power law exponent and conductor-insulator fraction. The model and numerical methods presented are considered a simple approach to interpret and predict and the frequency dependent properties of materials which similar heterogeneity
SN  - 0015-0193
M3  - doi:10.1080/00150190802381522
UR  - http://dx.doi.org/10.1080/00150190802381522
L2  - http://dx.doi.org/10.1080/00150190802381522
ER  -