Effect of topologically close-packed clusters on glass-forming ability of rapidly supercooled MgCuY alloy

Journal of Materials Research and Technology

Ze-an Tian¹  Ting-hong Gao²  Qian Chen²  Li-li Zhou³  Jia-jun Ma⁴  Yun-fei Mo⁴  Yuan-wei Pu⁴  Quan Xie⁴  Yong-chao Liang⁴  Li Zhang⁴  Rang-su Liu⁵ 

[1] Corresponding author.;College of Computer Science and Electronic Engineering, Hunan University, Changsha, 410082, China;Department of Information Engineering, Gannan Medical University, Ganzhou, 341000, China;Institute of Advanced Optoelectronic Materials and Technology, School of Big Data and Information Engineering, Guizhou University, Guiyang, 550025, China;School of Electronic and Communication Engineering, Changsha University, Changsha, 410003, China;

关键词: Molecular dynamics simulation;    Glass-forming ability;    TCP nanocluster;    Dynamic characteristics;   

DOI  :  

来源: DOAJ

【 摘 要 】

The glass-forming ability (GFA) of metallic glasses can be enhanced by adding trace elements, but it is difficult to explain the reasons from microcosmic viewpoint due to the limitation of experimental conditions. Therefore, in order to reveal the effects of trace elements on GFA, the rapid solidification process of Mg65Cu(35-x)Yx (x = 5,10,15,20,25) ternary alloys are simulated by molecular dynamics (MD) in this paper, then the short- and medium-range order, thermodynamics and dynamics are investigated. The average atomic potential energy shows that the GFA becomes stronger monotonically with the increase of Y element. S433 and S544 can evolve into S555 with higher fivefold symmetry and packing density during solidification, which the topologically close-packed (TCP) clusters are mainly composed of S555. And the higher TCP clusters system has stronger GFA, because TCP clusters are easy to connect with each other to form large-sized nanoclusters, and the larger size nanoclusters have a smaller average displacement, which hinders the crystallization. As TCP atoms with slower dynamic characteristics than other atoms, the dynamics with higher Y element becomes slower with the increase of TCP clusters, and thus adding Y element plays a promoting role for GFA.

【 授权许可】

Unknown