Dual-phase metallic glass and its two-dimensional fractal morphology

A dual-phase Y-W metallic glass is observed in nanoscaled Y-W multilayered films upon 200 keV xenon ion irradiation. Diffraction analysis and bright field images reveal that the metallic glass consists of separated glass phases evolved from the Y and W lattices, respectively, through spinodal decomposition, and that the glass features a two-dimensional fractal morphology consisting of the W-based glass phase branches sitting on the Y-based glass substrate. The fractal dimension is determined to be 1.75 ± 0.05, suggesting that the fractal is grown through a cluster-diffusion-limited-aggregation model. Moreover, based on a newly derived n-body Y-W potential, atomistic simulations confirm the possibility of metallic glass formation in the equilibrium immiscible Y-W system.