In-situ and ex-situ synchrotron X-ray diffraction studies of microstructural length scale controlled dealloying

Song, T.1; Yan, M.2,3; Webster, N. A. S.4; Styles, M. J.5; Kimpton, J. A.6; Qian, M.1

2019-04-15

10.1016/j.actamat.2019.02.019

ACTA MATERIALIA   影响因子和分区

1359-6454

1873-2453

This paper reports the critical role of microstructural length scale in dealloying for the fabrication of bimodal or monolithic functional nanoporous metal structures and the underlying mechanisms and kinetics. Two dual-phased (Al2Cu-AlCu) precursor alloys Al65Cu35 and Al55Cu45 (at.%) were selected to demonstrate the concept. Microstructural observations revealed that the two constituent phases Al2Cu and AlCu in each alloy can undergo either sequential dealloying, which leads to bimodal nanoporous Cu, or simultaneous dealloying, which results in monolithic nanoporous Cu. In-situ and ex-situ synchrotron Xray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), and potentiodynamic polarization scans were used to identify the detailed phase evolution processes and kinetics. It is concluded that microstructural length scale plays a decisive role in regulating the dealloying pathways. Sequential dealloying of Al2Cu and AlCu occurs when both phases are micrometer-scaled, while simultaneous dealloying takes over when both phases are nanoscaled. The nanosize effect of Al2Cu and AlCu can override their intrinsic difference in electrochemical potential at the micro- or macro-scale, and the advantage of tetragonal Al2Cu over monoclinic AlCu in crystallographic transition to face-centered-cubic (FCC) Cu by dealloying. The high-resolution in-situ synchrotron XRD data revealed a two-stage kinetic process for dealloying of Al2Cu to Cu. The Avrami-Erofe'ev kinetic model provides an excellent description of each stage. The underlying rationales and implications are discussed. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Dealloying Length scale Nanoporous Synchrotron XRD Dealloying kinetics

SCI ; EI

英语

其他

Shenzhen Science and Technology Innovation Commission[ZDSYS201703031748354]

Materials Science ; Metallurgy & Metallurgical Engineering

Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering

WOS:000464086500033

PERGAMON-ELSEVIER SCIENCE LTD

20191006587755

Binary alloys ; Ion beams ; Kinetics ; Scanning electron microscopy ; Synchrotron radiation ; X ray diffraction

Classical Physics; Quantum Theory; Relativity:931 ; High Energy Physics:932.1 ; Particle Accelerators:932.1.1

MATERIALS SCIENCE

Web of Science

1.RMIT Univ, Sch Engn, Ctr Addit Mfg, Melbourne, Vic 3000, Australia
2.Southern Univ Sci & Technol, Dept Mat Sci & Engn, Shenzhen 518055, Peoples R China
3.Southern Univ Sci & Technol, Shenzhen Key Lab Addit Mfg High Performance Mat, Shenzhen 518055, Peoples R China
4.CSIRO Mineral Resources, Private Bag 10, Clayton, Vic 3169, Australia
5.CSIRO Mfg, Clayton, Vic 3168, Australia
6.ANSTO, Australian Synchrotron, Clayton, Vic 3168, Australia

Song, T.,Yan, M.,Webster, N. A. S.,et al. In-situ and ex-situ synchrotron X-ray diffraction studies of microstructural length scale controlled dealloying[J]. ACTA MATERIALIA,2019,168:376-392.

Song, T.,Yan, M.,Webster, N. A. S.,Styles, M. J.,Kimpton, J. A.,&Qian, M..(2019).In-situ and ex-situ synchrotron X-ray diffraction studies of microstructural length scale controlled dealloying.ACTA MATERIALIA,168,376-392.

Song, T.,et al."In-situ and ex-situ synchrotron X-ray diffraction studies of microstructural length scale controlled dealloying".ACTA MATERIALIA 168(2019):376-392.