Atomic-scale structural evolution in selective laser melting of Cu50Zr50 metallic glass

Selective laser melting (SLM) provides a promising alternative to overcome the size and geometry limitation in the fabrication of metallic glasses (MGs). Understanding the change of atomic-scale structure is vital to glass formation and the properties of SLM-fabricated MGs. In this work, atomic structural evolution of Cu50Zr50 MG fabricated by SLM was investigated using molecular dynamics simulations. Voronoi tessellation analysis indicates that icosahedron-like clusters and Frank-Kasper polyhedra are dominant in cladding and deposited layers. In addition, the fractions of populous icosahedron- like clusters decrease in molten pool while slightly increase in heat affected zone during SLM process, and the fractions of populous Frank-Kasper polyhedra remain virtually unchanged after laser melting and heat affecting. This work provides a necessary understanding and novel guidance to the fabrication of MGs using SLM.