Unveiling the mechanism of phase and morphology selections during the devitrification of Al-Sm amorphous ribbon

The complex interplay between energetic and kinetic factors that governs the phase morphology selections can originate at earliest stage of crystallization in amorphous parent phases. Because extreme difficulties capturing microscopic nucleation process, a detailed picture how initial disordered structures affect transformation pathway remains unclear. Here, we report experimental observation widely varying selection grain size evolution during devitrification homogeneous melt-spun glassy ribbon. Two different crystalline phases $\ensuremath{\theta}\text{\ensuremath{-}}{\mathrm{Al}}_{5}\mathrm{Sm}$ $\ensuremath{\varepsilon}\text{\ensuremath{-}}{\mathrm{Al}}_{60}{\mathrm{Sm}}_{11}$ are found to form regions same metallic glass (MG) ribbon devitrification. shows strong spatial heterogeneity. coarse-grained coupled with small volume fraction is preferably formed close wheel side Combining characterization computational simulations, show microstructure be traced back types populations atomic clusters serve as precursors for Inhomogeneous cooling rates cause structure orders across sample quenching process. Our findings provide direct insight into effect structural order on pathways MG. It also opens an avenue study process level using MG platform suggests opportunity property design via controlling