Abstrato

Effect of Temperature and Phase on Properties of Metal Pseudobrookite

S. S. Gurav and S. V. Salvi

Iron titanate is a metal pseudobrookite, which exhibits many interesting properties such as spin glass behaviour, thermal microcracking, magnetic texture and high resistivity. The polycrystalline pseudobrookite has wide range of applications. This communication presents the comparative study of electrical resistivity and dielectric properties as a function of temperature and relaxation spectra of pure iron titanates prepared by using rutile form of titanium oxide and sintered at two temperatures viz. 1000oC and 1250oC and also prepared at 1250oC using anatase form of titanium oxide.

The iron titanates are synthesized by usual standard ceramic technique using A.R. grade oxides. The single phase formation is confirmed by XRD and FTIR techniques. Structurally all the samples remain as pseudobrookite having orthorhombic unit cell.

The analysis of the relaxation spectra establishes the presence of space-charge, which increases with the sintering temperature for the pseudobrookite prepared from rutile TiO2. Also the analysis shows that the pseudobrookite prepared from anatase TiO2 has lower dielectric and electric properties at low frequency (1 kHz) and shows pronounced hysteresis indicating lower microcrack healing. The changes in the resistivity, dielectric constant and dielectric loss are discussed and analysed on the basis of structural changes.