Computation assisted design of favored composition for ternary Mg-Cu-Y metallic glass formation.

摘要: With the aid of ab initio calculations, a realistic interatomic potential was constructed for Mg–Cu–Y ternary system under proposed formalism smoothed and long-range second-moment approximation tight-binding. Taking as starting base, an atomistic computation/simulation route developed designing favored optimized compositions metallic glass formation. Simulations revealed that physical origin formation is collapse crystalline lattice when solute concentration exceeds critical value, thus leading to predict hexagonal region in composition triangle, within which energetically favored. It can be defined intrinsic region, or quantitative ability system. Inside driving force each specific glassy alloy further calculated correlated with its forming practice. Calculations pinpointed stoichiometry Mg64Cu16Y20, at reaches maximum, suggesting glasses designed have around Mg64Cu16Y20 are most stable easiest obtain. The predictions derived directly from simulations supported by experimental observations reported so far literature. Furthermore, Honeycutt–Anderson analysis indicated pentagonal bipyramids (although not aggregating form icosahedra) dominate local structure glasses. A microscopic picture medium-range packing then described extended network bipyramids, entangled fourfold sixfold disclination lines, jointly fulfilling space