Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published September 18, 2015 | public
Journal Article Open

Fractal atomic-level percolation in metallic glasses


Metallic glasses are metallic alloys that exhibit exotic material properties. They may have fractal structures at the atomic level, but a physical mechanism for their organization without ordering has not been identified. We demonstrated a crossover between fractal short-range (<2 atomic diameters) and homogeneous long-range structures using in situ x-ray diffraction, tomography, and molecular dynamics simulations. A specific class of fractal, the percolation cluster, explains the structural details for several metallic-glass compositions. We postulate that atoms percolate in the liquid phase and that the percolating cluster becomes rigid at the glass transition temperature.

Additional Information

© 2015 American Association for the Advancement of Science. Received for publication 14 March 2015. Accepted for publication 31 July 2015. Diffraction data and simulated RDFs are available as supplementary materials. The authors thank D. C. Hofmann for providing the Cu_(46)Zr_(46)Al_5Be_3 wires and Y. Lin for her aid in sample loading. The authors acknowledge the financial support of the U.S. Department of Energy Office of Basic Energy Sciences (DOE-BES) and NASA's Space Technology Research Grants Program (Early Career Faculty grants to J.R.G.). W.L.M. and C.Y.S. acknowledge support from NSF grant EAR-1055454. Q.Z. acknowledges support from DOE-BES (grant DE-FG02-99ER45775) and the National Natural Science Foundation of China (grant U1530402). Portions of this work were performed at the High Pressure Collaborative Access Team (HPCAT) of the Advanced Photon Source (APS), Argonne National Laboratory. HPCAT operations are supported by DOE's National Nuclear Security Administration (NNSA) under award no. DE-NA0001974 and by DOE-BES under award no. DE-FG02-99ER45775, with partial instrumentation funding by NSF grant MRI-1126249. APS is supported by DOE-BES under contract no. DE-AC02-06CH11357. Portions of this research were carried out at the Stanford Synchrotron Radiation Lightsource, a directorate of SLAC National Accelerator Laboratory and an Office of Science User Facility operated for DOE by Stanford University. Some computations were carried out on the Shared Heterogeneous Cluster computers (Caltech Center for Advanced Computing Research) provided by the NNSA Predictive Science Academic Alliance Program at Caltech (grant DE-FC52-08NA28613) and on the NSF Center for Science and Engineering of Materials computer cluster (grant DMR-0520565). Q.A. and W.A.G. received support from the Defense Advanced Research Projects Agency–Army Research Office (grant W31P4Q-13-1-0010) and NSF (grant DMR-1436985). This material is based on work supported by an NSF Graduate Research Fellowship (grant DGE-1144469). Any opinions, findings, and conclusions or recommendations expressed in the material are those of the authors and do not necessarily reflect the views of NSF.

Attached Files

Supplemental Material - aab1233-Chen-SM-database-S1.rar

Supplemental Material - aab1233-Chen-SM-database-S2.rar

Supplemental Material - aab1233-Chen-SM-database-S3.rar

Supplemental Material - aab1233-Chen-SM-database-S4.rar

Supplemental Material - aab1233-Chen-SM.pdf


Files (731.1 kB)
Name Size Download all
33.7 kB Download
24.0 kB Download
104.7 kB Download
253.6 kB Download
315.1 kB Preview Download

Additional details

August 20, 2023
August 20, 2023