Abstract
We show that flash experiments with three phase mixed鈥恜owders of yttria stabilized zirconia (8YSZ), MgO, and 伪鈥怉l2O3聽not only produce polycrystals of high density, but also the transformation of magnesia and alumina into single phase spinel. The presence of zirconia facilitates the onset of the flash. The sintering experiments in the laboratory were extended to live experiments at the National Synchrotron Light Source II at Brookhaven National Laboratory in order to measure the time dependent evolution of single鈥恜hase spinel. The phase transformation occurred in less than 3 s during Stage II. Later, during Stage III the cubic zirconia transformed partly into the monoclinic phase, which reverted back to the cubic phase when the flash was extinguished by turning off the current to the specimen. The results underpin a recent report on the synthesis of single鈥恜hase bismuth ferrite from constituent oxides in reactive flash experiments, raising the specter of flash as a method for synthesis as well as sintering of complex oxide ceramics. The role of zirconia in catalyzing the flash in the present work is discussed.