Hidden amorphous phase and reentrant supercooled liquid in Pd-Ni-P metallic glasses

ARTICLE

Received 19 Jul 2016 | Accepted 19 Jan 2017 | Published 17 Mar 2017

S. Lan1,2, Y. Ren3, X.Y. Wei2, B. Wang2, E.P. Gilbert4, T. Shibayama5, S. Watanabe5, M. Ohnuma5 & X.-L. Wang2,6,7

An anomaly in differential scanning calorimetry has been reported in a number of metallic glass materials in which a broad exothermal peak was observed between the glass and crystallization temperatures. The mystery surrounding this calorimetric anomaly is epitomized by four decades long studies of Pd-Ni-P metallic glasses, arguably the best glass-forming alloys. Here we show, using a suite of in situ experimental techniques, that Pd-Ni-P alloys have a hidden amorphous phase in the supercooled liquid region. The anomalous exothermal peak is the consequence of a polyamorphous phase transition between two supercooled liquids, involving a change in the packing of atomic clusters over medium-range length scales as large as 18 . With further temperature increase, the alloy reenters the supercooled liquid phase, which forms the room-temperature glass phase on quenching. The outcome of this study raises a possibility to manipulate the structure and hence the stability of metallic glasses through heat treatment.

DOI: 10.1038/ncomms14679 OPEN

Hidden amorphous phase and reentrant supercooled liquid in Pd-Ni-P metallic glasses

1 Herbert Gleiter Institute of Nanoscience, Nanjing University of Science and Technology, 200 Xiaolingwei Avenue, Nanjing 210094, China. 2 Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China. 3 X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA. 4 Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization (ANSTO), Locked Bag 2001, Kirrawee DC NSW 2232, Australia. 5 Laboratory of Quantum Beam System, Division of Quantum Beam Engineering, Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Sapporo 060-8628, Japan. 6 City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Shenzhen 518057, China. 7 Center for Advanced Structural Materials, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China. Correspondence and requests for materials should be addressed to X.-L.W. (email: mailto:[email protected]

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NATURE COMMUNICATIONS | 8:14679 | DOI: 10.1038/ncomms14679 | http://www.nature.com/naturecommunications

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ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/ncomms14679

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Pd-Ni-P is an excellent glass-forming system, for which centimetre-sized metallic...