Understanding the formation of (Al,Si)3Sc and V-phase (AlSc2Si2) in Al-Si-Sc alloys via ex situ heat treatments and in situ transmission electron microscopy studies

Jayshri Dumbre; Shravan K. Kairy; Elaf Anber; Timothy Langan; Mitra L. Taheri; Thomas Dorin; Nick Birbilis

doi:10.1016/j.jallcom.2020.158511

Understanding the formation of (Al,Si)₃Sc and V-phase (AlSc₂Si₂) in Al-Si-Sc alloys via ex situ heat treatments and in situ transmission electron microscopy studies

Jayshri Dumbre
, Shravan K. Kairy
, Elaf Anber
, Timothy Langan
, Mitra L. Taheri
, Thomas Dorin
, Nick Birbilis

Materials Science & Engineering

Research output: Contribution to journal › Article › Research › peer-review

45 Citations (Scopus)

Abstract

Scandium (Sc) containing Al-Si model alloys were heat-treated at various temperatures to determine the interaction between Si and Sc. The (Al,Si)₃Sc phase was formed at ~350 °C and V-phase (AlSc₂Si₂) was observed to form at above ~450 °C, as determined from x-ray diffraction and selected area electron diffraction. Hardening of the alloys was observed due to the formation of coherent, nanoscale (Al,Si)₃Sc precipitates; whereas significant softening was observed upon the formation of coarse V-phase. Herein, the V-phase is studied in detail and has for the first time been revealed to have a rod morphology. The Transmission electron microscopy (TEM) allowed for the determination of six new orientation relationships (ORs) with the α-Al matrix for the V-phase. Additionally, in situ TEM heating experiments at 550 °C revealed that the formation of V-phase occurs due to a nucleation and growth mechanism following the dissolution of Si particles and nanoscale (Al,Si)₃Sc precipitates.

Original language	English
Article number	158511
Number of pages	13
Journal	Journal of Alloys and Compounds
Volume	861
DOIs	https://doi.org/10.1016/j.jallcom.2020.158511
Publication status	Published - 25 Apr 2021

Keywords

Metals and alloys
Microstructure
Precipitation
Transmission electron microscopy (TEM)

Access to Document

10.1016/j.jallcom.2020.158511

Cite this

@article{a790cc81fb4b4757a771301424436460,

title = "Understanding the formation of (Al,Si)3Sc and V-phase (AlSc2Si2) in Al-Si-Sc alloys via ex situ heat treatments and in situ transmission electron microscopy studies",

abstract = "Scandium (Sc) containing Al-Si model alloys were heat-treated at various temperatures to determine the interaction between Si and Sc. The (Al,Si)3Sc phase was formed at \textasciitilde{}350 °C and V-phase (AlSc2Si2) was observed to form at above \textasciitilde{}450 °C, as determined from x-ray diffraction and selected area electron diffraction. Hardening of the alloys was observed due to the formation of coherent, nanoscale (Al,Si)3Sc precipitates; whereas significant softening was observed upon the formation of coarse V-phase. Herein, the V-phase is studied in detail and has for the first time been revealed to have a rod morphology. The Transmission electron microscopy (TEM) allowed for the determination of six new orientation relationships (ORs) with the α-Al matrix for the V-phase. Additionally, in situ TEM heating experiments at 550 °C revealed that the formation of V-phase occurs due to a nucleation and growth mechanism following the dissolution of Si particles and nanoscale (Al,Si)3Sc precipitates.",

keywords = "Metals and alloys, Microstructure, Precipitation, Transmission electron microscopy (TEM)",

author = "Jayshri Dumbre and Kairy, \{Shravan K.\} and Elaf Anber and Timothy Langan and Taheri, \{Mitra L.\} and Thomas Dorin and Nick Birbilis",

note = "Funding Information: The authors acknowledge the use of instruments and scientific and technical assistance at the Monash Centre for Electron Microscopy, a Node of Microscopy Australia and Monash X-Ray Platform (XRP), Monash University, Australia. This research used equipment funded by the Australian Research Council Grant ( LE110100223 ). The authors are grateful to Clean TeQ Holdings Ltd., Australia for providing Al-Sc master alloys and acknowledge financial support through the ARC Linkage Project Scheme ( LP160100104 ). Dr Thomas Dorin is the recipient of an Australian Research Council - Australian Discovery Early Career Award. The authors also acknowledge the use of the Centralized Research Facility (CRF) at Drexel University, Philadelphia, USA for in situ TEM experiments. Funding Information: The authors acknowledge the use of instruments and scientific and technical assistance at the Monash Centre for Electron Microscopy, a Node of Microscopy Australia and Monash X-Ray Platform (XRP), Monash University, Australia. This research used equipment funded by the Australian Research Council Grant (LE110100223). The authors are grateful to Clean TeQ Holdings Ltd. Australia for providing Al-Sc master alloys and acknowledge financial support through the ARC Linkage Project Scheme (LP160100104). Dr Thomas Dorin is the recipient of an Australian Research Council - Australian Discovery Early Career Award. The authors also acknowledge the use of the Centralized Research Facility (CRF) at Drexel University, Philadelphia, USA for in situ TEM experiments. Publisher Copyright: {\textcopyright} 2021 Elsevier B.V.",

year = "2021",

month = apr,

day = "25",

doi = "10.1016/j.jallcom.2020.158511",

language = "English",

volume = "861",

journal = "Journal of Alloys and Compounds",

issn = "0925-8388",

publisher = "Elsevier BV",

}

Understanding the formation of (Al,Si)₃Sc and V-phase (AlSc₂Si₂) in Al-Si-Sc alloys via ex situ heat treatments and in situ transmission electron microscopy studies. / Dumbre, Jayshri; Kairy, Shravan K.; Anber, Elaf et al.
In: Journal of Alloys and Compounds, Vol. 861, 158511, 25.04.2021.

Research output: Contribution to journal › Article › Research › peer-review

TY - JOUR

T1 - Understanding the formation of (Al,Si)3Sc and V-phase (AlSc2Si2) in Al-Si-Sc alloys via ex situ heat treatments and in situ transmission electron microscopy studies

AU - Dumbre, Jayshri

AU - Kairy, Shravan K.

AU - Anber, Elaf

AU - Langan, Timothy

AU - Taheri, Mitra L.

AU - Dorin, Thomas

AU - Birbilis, Nick

N1 - Funding Information: The authors acknowledge the use of instruments and scientific and technical assistance at the Monash Centre for Electron Microscopy, a Node of Microscopy Australia and Monash X-Ray Platform (XRP), Monash University, Australia. This research used equipment funded by the Australian Research Council Grant ( LE110100223 ). The authors are grateful to Clean TeQ Holdings Ltd., Australia for providing Al-Sc master alloys and acknowledge financial support through the ARC Linkage Project Scheme ( LP160100104 ). Dr Thomas Dorin is the recipient of an Australian Research Council - Australian Discovery Early Career Award. The authors also acknowledge the use of the Centralized Research Facility (CRF) at Drexel University, Philadelphia, USA for in situ TEM experiments. Funding Information: The authors acknowledge the use of instruments and scientific and technical assistance at the Monash Centre for Electron Microscopy, a Node of Microscopy Australia and Monash X-Ray Platform (XRP), Monash University, Australia. This research used equipment funded by the Australian Research Council Grant (LE110100223). The authors are grateful to Clean TeQ Holdings Ltd. Australia for providing Al-Sc master alloys and acknowledge financial support through the ARC Linkage Project Scheme (LP160100104). Dr Thomas Dorin is the recipient of an Australian Research Council - Australian Discovery Early Career Award. The authors also acknowledge the use of the Centralized Research Facility (CRF) at Drexel University, Philadelphia, USA for in situ TEM experiments. Publisher Copyright: © 2021 Elsevier B.V.

PY - 2021/4/25

Y1 - 2021/4/25

N2 - Scandium (Sc) containing Al-Si model alloys were heat-treated at various temperatures to determine the interaction between Si and Sc. The (Al,Si)3Sc phase was formed at ~350 °C and V-phase (AlSc2Si2) was observed to form at above ~450 °C, as determined from x-ray diffraction and selected area electron diffraction. Hardening of the alloys was observed due to the formation of coherent, nanoscale (Al,Si)3Sc precipitates; whereas significant softening was observed upon the formation of coarse V-phase. Herein, the V-phase is studied in detail and has for the first time been revealed to have a rod morphology. The Transmission electron microscopy (TEM) allowed for the determination of six new orientation relationships (ORs) with the α-Al matrix for the V-phase. Additionally, in situ TEM heating experiments at 550 °C revealed that the formation of V-phase occurs due to a nucleation and growth mechanism following the dissolution of Si particles and nanoscale (Al,Si)3Sc precipitates.

AB - Scandium (Sc) containing Al-Si model alloys were heat-treated at various temperatures to determine the interaction between Si and Sc. The (Al,Si)3Sc phase was formed at ~350 °C and V-phase (AlSc2Si2) was observed to form at above ~450 °C, as determined from x-ray diffraction and selected area electron diffraction. Hardening of the alloys was observed due to the formation of coherent, nanoscale (Al,Si)3Sc precipitates; whereas significant softening was observed upon the formation of coarse V-phase. Herein, the V-phase is studied in detail and has for the first time been revealed to have a rod morphology. The Transmission electron microscopy (TEM) allowed for the determination of six new orientation relationships (ORs) with the α-Al matrix for the V-phase. Additionally, in situ TEM heating experiments at 550 °C revealed that the formation of V-phase occurs due to a nucleation and growth mechanism following the dissolution of Si particles and nanoscale (Al,Si)3Sc precipitates.

KW - Metals and alloys

KW - Microstructure

KW - Precipitation

KW - Transmission electron microscopy (TEM)

UR - https://www.scopus.com/pages/publications/85099189253

U2 - 10.1016/j.jallcom.2020.158511

DO - 10.1016/j.jallcom.2020.158511

M3 - Article

AN - SCOPUS:85099189253

SN - 0925-8388

VL - 861

JO - Journal of Alloys and Compounds

JF - Journal of Alloys and Compounds

M1 - 158511

ER -

Understanding the formation of (Al,Si)₃Sc and V-phase (AlSc₂Si₂) in Al-Si-Sc alloys via ex situ heat treatments and in situ transmission electron microscopy studies

Abstract

Keywords

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Advanced in-situ electron microscope facility for research in alloys, nanomaterials, functional materials, magnetic materials and minerals

Monash Centre for Electron Microscopy (MCEM)

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Understanding the formation of (Al,Si)3Sc and V-phase (AlSc2Si2) in Al-Si-Sc alloys via ex situ heat treatments and in situ transmission electron microscopy studies

Abstract

Keywords

Access to Document

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Projects

Advanced in-situ electron microscope facility for research in alloys, nanomaterials, functional materials, magnetic materials and minerals

Equipment

Monash Centre for Electron Microscopy (MCEM)

Cite this

Understanding the formation of (Al,Si)₃Sc and V-phase (AlSc₂Si₂) in Al-Si-Sc alloys via ex situ heat treatments and in situ transmission electron microscopy studies