Crystallization of phase-separated Pd_41.25Ni _41.25P_17.5 BMGs

Phase-separated Pd_41.25Ni_41.25P_17.5 bulk metallic glasses (BMGs) were subjected to isothermal annealing at 613 K (340 °C) for different time periods, t, in the range of 0 ≤ t ≤ 8 hours. For 0 ≤ t ≤ 5 hours, crystalline precipitates, in the shape of spheres, appear and its density is more or less a linear function of t. They are randomly distributed in the amorphous matrix. For t ≥ 5 to 6 hours, the number density of the spherical crystalline precipitates increases rapidly. In addition, they are no longer distributed randomly in the phase-separated amorphous matrix. Clustering is displayed. Experimental results suggest that the clustering is due to cubic crystalline precipitates that start to appear when t ≈ 5 to 6 hours.