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Author (up) Wang, X.; Li, K.; Schryvers, D.; Verlinden, B.; Van Humbeeck, J.
Title R-phase transition and related mechanical properties controlled by low-temperature aging treatment in a Ti50.8 at.% Ni thin wire Type A1 Journal article
Year 2014 Publication Scripta materialia Abbreviated Journal Scripta Mater
Volume 72-73 Issue Pages 21-24
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A cold-drawn Ti50.8 at.% Ni wire was annealed at 600 °C for 30 min, followed by aging at 250 °C for different times. A microstructure with small grains and nanoscaled precipitates was obtained. The thermally induced martensite transformation is suppressed in the samples aged for 4 h or longer, leaving a one-stage R-phase transition between −150 and +150 °C. The transformation behavior, work output and recovery stress associated with the R-phase transition are presented.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000329148500006 Publication Date 2013-10-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6462; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.747 Times cited 27 Open Access
Notes Fwo Approved Most recent IF: 3.747; 2014 IF: 3.224
Call Number UA @ lucian @ c:irua:111847 Serial 2806
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Author (up) Wang, X.; Yao, X.; Schryvers, D.; Verlinden, B.; Wang, G.; Zhao, G.; Van Humbeeck, J.; Kustov, S.
Title Anomalous stress-strain behavior of NiTi shape memory alloy close to the border of superelastic window Type A1 Journal article
Year 2021 Publication Scripta Materialia Abbreviated Journal Scripta Mater
Volume 204 Issue Pages 114135
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In this work, we report an anomalous phenomenon on superelastic cycling of NiTi shape memory alloys when deforming at the temperature close to the border of superelastic window. New unexpected effects are found-(i) critical stress for inducing martensite transformation during the second loading cycle is higher than that of the first cycle; ( ii ) the plateau stress of the second cycle decreases to the original level when the strain overcomes the limit of the first cycle; ( iii ) transition from good superelasticity in the first cycle to fully irreversible strain in the second. We propose that defects generated during the first superelastic cycle close to the border of superelastic window impede following stress-induced martensitic transformations, leading to the increase of critical stress beyond yield stress of the B2 matrix, and thus functional fatigue of NiTi alloys. (c) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000690441400007 Publication Date 2021-07-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6462 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.747 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.747
Call Number UA @ admin @ c:irua:181658 Serial 6853
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Author (up) Weng, Y.; Ding, L.; Zhang, Z.; Jia, Z.; Wen, B.; Liu, Y.; Muraishi, S.; Li, Y.; Liu, Q.
Title Effect of Ag addition on the precipitation evolution and interfacial segregation for Al-Mg-Si alloy Type A1 Journal article
Year 2019 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 180 Issue 180 Pages 301-316
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The effect of Ag addition on the precipitation evolution and interfacial segregation for Al-Mg-Si alloys was systematically investigated by atomic resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), atom probe tomography (APT) and density functional theory (DFT) calculation. At the early aging stage, Ag atoms could enter clusters and refine the distribution of these clusters. Then, Ag atoms preferentially segregate at the GP zone/alpha-Al and beta ''/alpha-Al interfaces at the peak aging stage by the replacement of Al atoms in FCC matrix. With prolonging aging time, Ag atoms generally incorporate into the interior of beta '' precipitate, facilitating the formation of QP lattice (a hexagonal network of Si atomic columns) and the local symmetry substructures, Ag sub-unit (1) and Ag sub-unit (2). At the over-aged stage, the Ag sub-unit (1) and Ag sub-unit (2) could transform to the beta'(Ag) (i.e. beta'(Ag1) and beta'(Ag2).) and Q'(Ag) unit cells, respectively. All the precipitates at the over-aging stage have a composite and disordered structure due to the coexistence of different unit cells (beta'(Ag1), beta'(Ag2), Q'(Ag) and beta') and the non-periodic arrangement of Ag atoms within the precipitate. In the equilibrium stage, the incorporated Ag atoms in the precipitates release into the alpha-Al matrix as solute atoms or form Ag particles. In general, Ag atoms undergo a process of “segregate at the precipitate/matrix interface -> incorporate into the interior of precipitate -> release into the alpha-Al matrix” during the precipitation for Al-Mg-Si-Ag alloys. Besides, Ag segregation is found at the interfaces of almost all metastable phases (including GP zone, beta '', beta'/beta'(Ag) phase) in Al-Mg-Si-Ag alloys. The Ag segregation at the beta'/alpha-Al interface could increase the length/diameter ratio of beta' phase and thus promote the additional strengthening potential of these alloys. These findings provide a new route for precipitation hardening by promoting the nucleation and morphology evolution of precipitates. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000495519100028 Publication Date 2019-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6454 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.301 Times cited Open Access
Notes Approved Most recent IF: 5.301
Call Number UA @ admin @ c:irua:164641 Serial 6295
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Author (up) Yang, M.; Orekhov, A.; Hu, Z.-Y.; Feng, M.; Jin, S.; Sha, G.; Li, K.; Samaee, V.; Song, M.; Du, Y.; Van Tendeloo, G.; Schryvers, D.
Title Shearing and rotation of β'' and β' precipitates in an Al-Mg-Si alloy under tensile deformation : in-situ and ex-situ studies Type A1 Journal article
Year 2021 Publication Acta Materialia Abbreviated Journal Acta Mater
Volume 220 Issue Pages 117310
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The interaction between dislocations and nano-precipitates during deformation directly influences hardening response of precipitation-strengthening metals such as Al-Mg-Si alloys. However, how coherent and semi-coherent nano-precipitates accommodate external deformation applied to an Al alloy remains to be elucidated. In-situ tensile experiments in a transmission electron microscope (TEM) were conducted to study the dynamic process of dislocations cutting through coherent needle-like beta '' precipitates with diameters of 3 similar to 8 nm. Comprehensive investigations using in-situ, ex-situ TEM and atom probe tomography uncovered that beta '' precipitates were firstly sheared into small fragments, and then the rotation of the fragments, via sliding along precipitate/matrix interfaces, destroyed their initially coherent interface with the Al matrix. In contrast, semi-coherent beta' precipitates with sizes similar to beta '' were more difficult to be fragmented and accumulation of dislocations at the interface increased interface misfit between beta' and the Al matrix. Consequently, beta' precipitates could basically maintain their needle-like shape after the tensile deformation. This research gains new insights into the interaction between nano-precipitates and dislocations. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000705535300005 Publication Date 2021-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6454 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.301 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 5.301
Call Number UA @ admin @ c:irua:182528 Serial 6884
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Author (up) Yang, T.; Kong, Y.; Du, Y.; Li, K.; Schryvers, D.
Title Discovery of core-shell quasicrystalline particles Type A1 Journal article
Year 2023 Publication Scripta materialia Abbreviated Journal
Volume 222 Issue Pages 115040-115046
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Submicron-sized quasicrystalline particles were obtained in an Al-Zn-Mg-Cu alloy produced by traditional melting. These particles consist of an Al-Fe-Ni core and a Mg-Cu-Zn shell and were found to be stable and embedded randomly in the Al matrix. The diffraction patterns of these core-shell particles reveal a decagonal core and an icosahedral shell with, respectively, ten- and five-fold axes aligned. High resolution scanning transmission electron microscopy of the Mg-Cu-Zn shell confirms the five-fold symmetry atomic arrangement and the icosahedral structure. It can therefore be concluded that Fe and Ni impurities play an important role in mediating the formation of such an unusual ternary core-shell quasicrystalline particle. These findings provide some novel insights in the formation of quasicrystals in traditional industrial Al alloys.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000864491400005 Publication Date 2022-09-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6462 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 6; 2023 IF: 3.747
Call Number UA @ admin @ c:irua:191489 Serial 7144
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Author (up) Yang, Z.; Tirry, W.; Lamoen, D.; Kulkova, S.; Schryvers, D.
Title Electron energy-loss spectroscopy and first-principles calculation studies on a Ni-Ti shape memory alloy Type A1 Journal article
Year 2008 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 56 Issue 3 Pages 395-404
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000253020900011 Publication Date 2007-12-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6454; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.301 Times cited 20 Open Access
Notes Goa; Ec Rtn; Fwo Approved Most recent IF: 5.301; 2008 IF: 3.729
Call Number UA @ lucian @ c:irua:67462 Serial 931
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Author (up) Yang, Z.; Tirry, W.; Schryvers, D.
Title Analytical TEM investigations on concentration gradients surrounding Ni4Ti3 precipitates in Ni-Ti shape memory material Type A1 Journal article
Year 2005 Publication Scripta materialia Abbreviated Journal Scripta Mater
Volume 52 Issue 11 Pages 1129-1134
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000228190200010 Publication Date 2005-03-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6462; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.747 Times cited 49 Open Access
Notes GOA project; MCRTN-FP6-505226 Multimat Approved Most recent IF: 3.747; 2005 IF: 2.228
Call Number UA @ lucian @ c:irua:55687 Serial 110
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Author (up) Zhang, F.; Batuk, M.; Hadermann, J.; Manfredi, G.; Mariën, A.; Vanmeensel, K.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J.
Title Effect of cation dopant radius on the hydrothermal stability of tetragonal zirconia: Grain boundary segregation and oxygen vacancy annihilation Type A1 Journal article
Year 2016 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 106 Issue 106 Pages 48-58
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The hydrothermal aging stability of 3Y-TZP-xM2O3 (M = La, Nd, Sc) was investigated as a function of 0.02–5 mol% M2O3 dopant content and correlated to the overall phase content, t-ZrO2 lattice parameters, grain size distribution, grain boundary chemistry and ionic conductivity.

The increased aging stability with increasing Sc2O3 content and the optimum content of 0.4–0.6 mol% Nd2O3 or 0.2–0.4 mol% La2O3, resulting in the highest aging resistance, could be directly related to the constituent phases and the lattice parameters of the remaining tetragonal zirconia.

At low M2O3 dopant contents ≤0.4 mol%, the different aging behavior of tetragonal zirconia was attributed to the defect structure of the zirconia grain boundary which was influenced by the dopant cation radius. It was observed that the grain boundary ionic resistivity and the aging resistance followed the same trend: La3+ > Nd3+ > Al3+ > Sc3+, proving that hydrothermal aging is driven by the diffusion of water-derived mobile species through the oxygen vacancies. Accordingly, we elucidated the underlying mechanism by which a larger trivalent cation segregating at the zirconia grain boundary resulted in a higher aging resistance.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000371650300006 Publication Date 2016-01-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6454 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.301 Times cited 37 Open Access
Notes The authors acknowledge the Research Fund of KU Leuven under project 0T/10/052 and the Fund for Scientific Research Flanders (FWO-Vlaanderen) under grant G.0431.10N. F. Zhang thanks the Research Fund of KU Leuven for her post-doctoral fellowship (PDM/15/153). Approved Most recent IF: 5.301
Call Number c:irua:132435 Serial 4076
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Author (up) Zhang, F.; Vanmeensel, K.; Batuk, M.; Hadermann, J.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J.
Title Highly-translucent, strong and aging-resistant 3Y-TZP ceramics for dental restoration by grain boundary segregation Type A1 Journal article
Year 2015 Publication Acta biomaterialia Abbreviated Journal Acta Biomater
Volume 16 Issue 16 Pages 215-222
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Latest trends in dental restorative ceramics involve the development of full-contour 3Y-TZP ceramics which can avoid chipping of veneering porcelains. Among the challenges are the low translucency and the hydrothermal stability of 3Y-TZP ceramics. In this work, different trivalent oxides (Al2O3, Sc2O3, Nd2O3 and La2O3) were selected to dope 3Y-TZP ceramics. Results show that dopant segregation was a key factor to design hydrothermally stable and high-translucent 3Y-TZP ceramics and the cation dopant radius could be used as a controlling parameter. A large trivalent dopant, oversized as compared to Zr4+, exhibiting strong segregation at the ZrO2 grain boundary was preferred. The introduction of 0.2 mol% La2O3 in conventional 0.10.25 wt.% Al2O3-doped 3Y-TZP resulted in an excellent combination of high translucency and superior hydrothermal stability, while retaining excellent mechanical properties.
Address
Corporate Author Thesis
Publisher Place of Publication S.l. Editor
Language Wos 000351978600021 Publication Date 2015-02-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-7061; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.319 Times cited 54 Open Access
Notes Fwo G043110n Approved Most recent IF: 6.319; 2015 IF: 6.025
Call Number c:irua:124421 Serial 1473
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Author (up) Zhang, Z.; Rosalie, J.M.; Medhekar, N.V.; Bourgeois, L.
Title Resolving the FCC/HCP interfaces of the \gamma'(Ag2Al) precipitate phase in aluminium Type A1 Journal article
Year 2019 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 174 Issue 174 Pages 116-130
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The gamma'(Ag2Al) phase in the Al-Ag alloy system has served as a textbook example for understanding phase transformations, precipitating hexagonal close-packed (HCP) crystals in the face-centred cubic (FCC) aluminium matrix. The gamma' precipitates display fully coherent interfaces at their broad facets and semicoherent interfaces at their edges. Shockley partial dislocations are expected to decorate the semicoherent interface due to the FCC-HCP structural transformation. Determining the exact locations and core structures of interfacial dislocations, however, remains challenging. In this study, we used aberration-corrected scanning transmission electron microscopy and atomistic simulations to re-visit this classical system. We characterised and explained the Ag segregation at coherent interfaces in the early stage of precipitation. For semicoherent interfaces, interfacial dislocations and reconstructions were revealed by bridging advanced microstructure characterisation and atomistic simulations. In particular, we discovered a new FCC/HCP interfacial structure that displays a unique combination of Shockley partial, Lomer-Cottrell and Hirth dislocations that evolve from the known interfacial structure purely composed by Shockley partial dislocations. Our findings show that the FCC-HCP transformation is more complex than hitherto considered, due to the interplay between structure and composition confined at interfaces. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000474501300011 Publication Date 2019-05-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6454 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.301 Times cited 3 Open Access
Notes ; The authors acknowledge funding from the Australian Research Council (LE0454166, LE110100223), the Victorian State Government and Monash University for instrumentation, and use of the facilities within the Monash Centre for Electron Microscopy. LB and NM acknowledge the financial support of the Australian Research Council (DP150100558). The authors also gratefully acknowledge the computational support from Monash Advanced Research Computing Hybrid, the National Computational Infrastructure and Pawsey Supercomputing Centre. ZZ is thankful to Monash University for a Monash Graduate Scholarship, a Monash International Postgraduate Research Scholarship and a Monash Centre for Electron Microscopy Postgraduate Scholarship. ZZ is indebted to Matthew Weyland for his training in aberration-corrected electron microscopy, Scott Findlay for his help on image simulations, Xiang Gao for alloy casting and Ian Polmear for discussions. ; Approved Most recent IF: 5.301
Call Number UA @ admin @ c:irua:161192 Serial 5395
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