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Since the discovery of the phenomenon of ferroelectricity in 1921, it had been only restricted to crystalline materials. An early attempt to describe a microscopic model of glassy ferroelectric was put forward, theoretically, by M. E. Lines, 1977. In this model, it was shown that there is no conceptual difficulty in perceiving the ferroelectric instability in the glassy state. The observation of ferroelectricity in bulky amorphous glassy compounds had not been experimentally realized until 2001 when the research behind this thesis was performed. This Master thesis introduces the first...

The polarization is the true measure of the degree of ferroelectricity. Generally, ceramic materials with high value of remanent polarization show usable piezoelectric effects. Accordingly, electric poling is one of the crucial intermediate stages of the manufacturing process of the piezoceramics devices. In this thesis, the ferroelectric, pyroelectric and piezoelectric properties and aftereffects in soft and hard PZT are studied. The properties can be influenced by various parameters either extrinsic such as an applied electric field or intrinsic such as grain size. The main objective of...