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A glass sample of composition Bi 1.8 Pb 0.3 Sr 2 Ca 2 Cu 2.8 K 0.2 O z was prepared by the conventional quenched-melt technique. The as-quenched sample has been confirmed to be amorphous by x-ray diffraction measurements. The scanning electron microscopy shows no sign of crystalline grain precipitation. Differential thermal analysis indicates a prominent endotherm at 530 K in addition to the glass transition at 607 K and crystallization at 717 K and melting at 1043 K. This extra endothermic peak could possibly be identified as due to a ferroelectric to paraelectric phase transition. This possibility was explored by performing electrical measurements, which include dielectric constant trace, polarization, and hysteresis loops measurements as a function of temperature. It was also found that the transition is irreversible if the glass-transition temperature was reached.

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