Physical properties of some multi component oxide Glasses

Abstract

Nearly, at the end of the last century an important scientific and technical •revolution in the field of manufacturing apparatuses and techniques was appeared. This was based already on both the advances in the study of electronic circuits and the scientific progress in the field of studying new materials specially amorphous and glassy solids. This reflects the importance of studying the physical properties of glasses specially those concerning with their ac and de electrical conductivity. However, in this work the ac and de electrical conduction was thoroughly investigated in a system of alkali-lead-borate containing iron ions. The composition was (70-x) mole Bz03 + x mole Pb304 + 10 mole Fe2 03 + 20 mole R2 0. where, R represents Li, Na and K respectively, and x = 0,5, I 0,15,20,25,30,35.and the preparation were carried out in porcelain crucibles at 950 °C for abut 90 minutes and annealed at 250 °C. The strtructual rule of the iron ions was firstly studied applying Mossbauer effect spectroscopy. From the obtained ME spectra it appeared that glasses free of lead show same precipitated iron oxide phase. On adding only 5 mole % lead oxide, the precipitated iron oxide phase disappeared completely. When adding more lead oxide, there is no effect appeared. The density values showed an increase with the increase of Pb304 content and the samples containing Li2 0 have the largest density values while the samples containing K2 0 showed the smallest density values.

The molar volume decreased with the gradual increase of lead oxide up to I 0 mole %, then it increase approximately linearly with lead oxide.