Role of Yttrium Substitution in the Atomic Cluster Evolution and Corrosion Behaviour of Al-Ni-Gd Metallic Glasses

摘要

Atomic cluster evolution and corrosion behaviour of Al84Ni10Gd6-xYx (x = 0, 2, 4 and 6) metallicglasses were investigated using experimental methods and ab initio molecular dynamic simulations.The shoulder peak area in x-ray diffraction patterns, enthalpy of second and third crystallization andpopulation of Ni-centered clusters increase with increasing yttrium content, but the onsettemperature and enthalpy of first crystallization decrease simultaneously. Yttrium substitution andannealing treatment can aggravate metastable pitting and induce a thicker alumina film duringpolarization, which can be explained by the segregation of Ni-centered clusters and ordering of Al-richclusters.