Atomic-Approach to Predict the Energetically Favored Composition Region and to Characterize the Short-, Medium-, and Extended-Range Structures of the Ti-Nb-Al Ternary Metallic Glasses

Bei Cai; Jianbo Liu; Jiahao Li; Menghao Yang; Baixin Liu

doi:10.3390/ma12030432

Atomic-Approach to Predict the Energetically Favored Composition Region and to Characterize the Short-, Medium-, and Extended-Range Structures of the Ti-Nb-Al Ternary Metallic Glasses

Materials (Basel). 2019 Jan 31;12(3):432. doi: 10.3390/ma12030432.

Authors

Bei Cai¹, Jianbo Liu², Jiahao Li³, Menghao Yang⁴, Baixin Liu⁵

Affiliations

¹ Key Laboratory of Advanced Materials (MOE), School of Materials science and Engineering, Tsinghua University, Beijing 100084, China. caib17@mails.tsinghua.edu.cn.
² Key Laboratory of Advanced Materials (MOE), School of Materials science and Engineering, Tsinghua University, Beijing 100084, China. jbliu@tsinghua.edu.cn.
³ Key Laboratory of Advanced Materials (MOE), School of Materials science and Engineering, Tsinghua University, Beijing 100084, China. lijiahao@tsinghua.edu.cn.
⁴ Ames Laboratory, US Department of Energy, Ames, IA 50011, USA. myang@ameslab.gov.
⁵ Key Laboratory of Advanced Materials (MOE), School of Materials science and Engineering, Tsinghua University, Beijing 100084, China. mslbx@tsinghua.edu.cn.

Abstract

Ab initio calculations were conducted to assist the construction of the n-body potential of the Ti-Nb-Al ternary metal system. Applying the constructed Ti-Nb-Al interatomic potential, molecular dynamics and Monte Carlo simulations were performed to predict a quadrilateral composition region, within which metallic glass was energetically favored to be formed. In addition, the amorphous driving force of those predicted possible glassy alloys was derived and an optimized composition around Ti₁₅Nb₄₅Al₄₀ was pinpointed, implying that this alloy was easier to be obtained. The atomic structure of Ti-Nb-Al metallic glasses was identified by short-, medium-, and extended-range analysis/calculations, and their hierarchical structures were responsible to the formation ability and unique properties in many aspects.

Keywords: Ti-Nb-Al system; atomic structure; atomistic simulation; glass-formation ability (GFA); interatomic potential.

Abstract

Grants and funding