BULK AMORPHOUS ZN-SB UNDER NORMAL AND HIGH-PRESSURES - PHASE-TRANSFORMATIONS AND RELAXATION PHENOMENA

Processes occurring upon heating of the high-pressure delta-Zn41Sb59 phase at atmospheric pressure were studied on bulk samples using scanning calorimetry and dilatometry in the temperature interval 170-573 K which includes the temperatures of amorphization and subsequent crystallization. Irreversible relaxation of the amorphous state followed by a heat release and elongation of the sample of the order of 1/4 of those found upon amorphization were observed at 325-425 K. At room temperature the effect of pressure on the electrical resistance of the amorphous Zn41Sb59 samples (P less-than-or-equal-to 70 kbar) and on their volume (P less-than-or-equal-to 28 kbar) was investigated. The resistance decreased with pressure by approximately five orders of magnitude displaying two falls at approximately 20 and 49 kbar characteristic of first-order phase transitions. The former transition was found to be reversible and is accompanied by an approximately 0.8% decrease in volume.