AUTHOR=Li Tian , Li Nana , Kuang Bo , Zheng Guangping 

TITLE=Molecular dynamics simulation on the mechanical properties of Zr-Cu metallic nanoglasses with heterogeneous chemical compositions

JOURNAL=Frontiers in Materials

VOLUME=11

YEAR=2024

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2024.1355522

DOI=10.3389/fmats.2024.1355522

ISSN=2296-8016

ABSTRACT=<p>The mechanical properties of metallic nanoglasses (NGs) strongly depend on the average size of glassy grains (D<sub>avg</sub>). Nevertheless, current knowledge on the effects of sizes of glassy grains is incomplete for the mechanical properties of NGs. Herein, Zr<sub>x</sub>Cu<sub>100-x</sub> (25 ≤ x ≤ 75) nanoglasses containing glassy grains with different chemical compositions, <italic>i.e.</italic>, the heterogeneous NGs (HNGs), are investigated by molecular dynamics simulation, and the relation between ultimate tensile strength (UTS) and D<sub>avg</sub> is determined. Specifically, the UTS decreases with decreasing D<sub>avg</sub> in Zr-Cu HNGs when D<sub>avg</sub> &lt; 10 nm, mainly resulting from the increased volume fraction of glass-glass interfaces, while UTS would follow the Hall–Petch like relation for Zr-Cu HNGs when D<sub>avg</sub> &gt; 10 nm, which is closely related to glassy grains with compositions dominated by Zr atoms. This study provides a deep insight into the mechanical property dependence on grain size in the HNGs, which could be a novel strategy in resolving the issue of strength-ductility tradeoff in NGs.</p>