الفهرس 
Theoretical considerationOnly 14 pages are availabe for public view
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Abstract
A two series of lead titanate with various concentration of zirconium (PbZrxTi1-xO3) (PZT), where (x= zero, 0.2, 0.4 and 0.8) and barium titanate with various concentration of samarium (BST), where (x = zero, 0.05, 0.1, 0.15, 0.2 and 0.3) have been prepared by tartrate precursor rout at different annealing temperatures, ranging from 600 to 1100 at atmospheric pressure. The XRD analyses of (PZT) samples confirm the presence of a single ferroelectric phase and for (BST) show the reflection of single phase perovskite structure. The FTIR spectra for (PZT) samples show two-vibrational main peaks at 585 and at 1385 , which are due to metal oxide bond vibration and to carbon oxygen vibration respectively and for (BST) samples show a strong absorption peak in (BT) powder is obtained around 580 cm-1 which is corresponding to stretching normal vibration of Ti- O octahedron. The DTA curve for the pure PbTiO3 shows an endothermic peace at about 480 which corresponds to the structural phase transition from the tetragonal to cubic phase. DC conductivity of PZT samples showed that the sample resistivity decrease with increasing temperature which confirming the semi conducting properties and for BST samples show the resistivity of all samples are very high which mean that the quality of our samples are highly resistive. The variation of Seebeck coefficient of PZT samples (α with temperature for all samples over temperature range (25 – 535) shows at room temperature the sample where found to be P-type semi-conductor, and for BST samples show the thermoelectric power exhibit positive sign for all samples which indicating the majority carriers are holes. The break point between two regions shifts to lower temperature. At low temperature the conduction obeys polaron hoping conduction between Ti4+ - Ti3+. The piezoelectric modulus d33 of PZT samples increased with increasing Zr content up to x = 0.4 and then decrease for higher content.