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Sains Malaysiana
39(6)(2010): 1007–1013
Dependence
of Pyroelectric Properties of La0.03Sr0.255Ba0.7Nb2-yTiyO(6-y/2) Ceramic on Electric Field, Grain Refinement and Ti/Nb
Crystallite Sizes
(Kebergantungan Sifat Piroelektrik Seramik La0.03Sr0.255Ba0.7Nb2-yTiyO(6-y/2) Terhadap Medan Elektrik
dan Saiz Hablur Ti/Nb)
Wee Chen Gan* & WanHaliza Abd. Majid
Solid State Research
Laboratory, Physics Department, University of Malaya
50603 Kuala Lumpur, Malaysia
Diserahkan: 14 Ogos
2009 / Diterima: 1 April 2010
ABSTRACT
The
pyroelectric properties of La0.03Sr0.255Ba0.7Nb2-yTiyO(6-y/2) (LSBNT) ceramic pellets using several Ti/Nb ratios sintered at 1250¡C
for 5 h were investigated. The samples were subjected to several values of
electric fields in order to obtain the optimum electric field strength. The
pyroelectric coefficients, (p) were measured using the quasi-static method by applying
several heating rates. The results show that the Ti/Nb ratios and the dc poling
field, (Edc) influenced the measured pyroelectric coefficient of the LSBNT ceramic
pellets. The mean grain size of the particles as obtained from scanning
electron microscope (SEM) does not seem to give significant impact on the pyroelectric
coefficient of the ceramic pellets. However, the X-Ray diffraction (XRD)
results indicate that the crystallite sizes of Ti and Nb of these ceramic
pellets after being treated with sintering process also influence the measured
pyroelectric coefficients of the ceramic pellets.
Keywords:
Ferroelectric ceramic; pyroelectric; spontaneous polarization
ABSTRAK
Sifat
piroelektrik La0.03Sr0.255Ba0.7Nb2-yTiyO(6-y/2) (LSBNT)
pelet seramik dengan nisbah Ti/Nb yang berlainan selepas dipanaskan pada suhu
1250¡C selama 5 jam telah dikaji. Sampel dikenakan medan elektrik yang
berlainan supaya ia mencapai keadaan medan elektrik yang optimum. Pekali
piroelektrik, (p) ditentukan dengan menggunakan kaedah kuasi-statik. Keputusan
yang didapati menunjukkan nisbah Ti/Nb dan medan kutub arus terus, (Edc)
mempengaruhi pekali piroelektrik seramik LSBNT yang dikaji. Saiz butiran
seperti yang didapati daripada mikroskop imbiasan elektron (SEM)
tidak menunjukkan sebarang pengaruh yang ketara terhadap pekalian piroelektrik
seramik. Bagaimanapun, keputusan pembiasan sinar-X (XRD) yang diperolehi menunjukkan saiz hablur Ti dan Nb seramik yang
telah dirawat dengan proses pemanasan menpengaruhi pekali piroelektrik seramik.
Kata
kunci: Pengutuban spontan; piroelektrik; seramik feroelektrik
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*Pengarang untuk surat-menyurat; email: wcgan1981@yahoo.com.sg
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