Relationship of glass forming ability and local structural properties of liquid Cu-Zr alloys  

作　　者：李敬芬 刘长松 

机构地区：[1]Key Laboratory of Materials Physics,Institute of Solid State Physics,Chinese Academy of Sciences [2]School of Physics and Material Science,Anhui University

出　　处：《Journal of Chongqing University》2011年第2期51-59,共9页重庆大学学报（英文版）

基　　金：Funded by the National Natural Science Foundation of China (Grant Nos. 11074253,10874182 and 50803066);the Foundation of the Education Committee of Anhui Province,China (Grant Nos. KJ2010A031 and KJ2010A012)

摘　　要：Molecular dynamics(MD) simulations were performed to investigate the glass forming ability(GFA) and microscopic structural properties of liquid Cu-Zr alloys.Based on the analysis of composition dependences of the reduced glass transition temperatures and the excess volume,we found that the Cu-Zr glasses have the largest GFA at Cu65Zr35 composition.To get more detailed information of local structure,we calculated the pair correlation functions,partial pair correlation functions,the excess entropy,chemical order parameter,coordination number,and Voronoi index of Cu-Zr liquids.We found that there exists an obvious and close relationship among the GFA,the excess entropy calculated using the total pair correlation functions,chemical order parameters,and some Cu centered cluster with Voronoi index <0,2,8,1> and Zr centered cluster with Voronoi index <0,3,6,4>,which all have nonlinear dependences on Cu/Zr concentration and have extreme values at liquid Cu65Zr35 composition.Molecular dynamics （MD） simulations were performed to investigate the glass forming ability （GFA） and microscopic structural properties of liquid Cu-Zr alloys. Based on the analysis of composition dependences of the reduced glass transition temperatures and the excess volume, we found that the Cu-Zr glasses have the largest GFA at Cu65Zr35 composition. To get more detailed information of local structure, we calculated the pair correlation functions, partial pair correlation functions, the excess entropy, chemical order parameter, coordination number, and Voronoi index of Cu-Zr liquids. We found that there exists an obvious and close relationship among the GFA, the excess entropy calculated using the total pair correlation functions, chemical order parameters, and some Cu centered cluster with Voronoi index 〈0,2,8,1〉 and Zr centered cluster with Voronoi index 〈0,3,6,4〉, which all have nonlinear dependences on Cu/Zr concentration and have extreme values at liquid Cu65Zr35 composition.

关 键 词：bulk metallic glass glass forming ability microscopic structure molecular dynamics simulation 

分 类 号：TG139.8[一般工业技术—材料科学与工程]