Kinetics of structure formation in the vicinity of the glass transition

The structural stability of a gold-based bulk metallic glass (Au49Ag5.5Pd2.3Cu26.9Si16.3) was investigated by fast differential scanning calorimetry (FDSC). A chemically homogeneous glass (CHG) containing no quenched-in nuclei was produced using sufficiently fast cooling from the melt. To characterize the stability of this glass, the structural variations during annealing in the glassy state were investigated and a sequence of five different events observed. These are structural relaxation, an incubation period, nucleation, crystallization, and finally reorganization. The kinetics of these processes and the stability of the crystalline structures are discussed.