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Author (up) Cao, S.; Zeng, C.Y.; Li, Y.Y.; Yao, X.; Ma, X.; Samaee, V.; Schryvers, D.; Zhang, X.P.
Title Quantitative FIB/SEM three-dimensional characterization of a unique Ni₄Ti₃ network in a porous Ni50.8Ti49.2 alloy undergoing a two-step martensitic transformation Type A1 Journal article
Year 2020 Publication Materials Characterization Abbreviated Journal Mater Charact
Volume 169 Issue Pages 110595
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The three-dimensional (3D) nanostructure of Ni4Ti3 precipitates in a porous Ni50.8Ti49.2 alloy has been re-constructed by “Slice-and-View” in a Focused Ion Beam/Scanning Electron Microscope (FIB/SEM). The 3D configuration of these precipitates forming a network structure in the B2 austenite matrix has been characterized via 3D visualization and quantitative analysis including volume fraction, skeleton, degree of anisotropy and local thickness. It is found that dense Ni4Ti3 precipitates occupy 54% of the volume in the B2 austenite matrix. Parallel Ni4Ti3 precipitates grow alongside the surface of a micro-pore, yielding an asymmetric structure, while nano voids do not seem to affect the growth of Ni4Ti3 precipitates. The small average local thickness of the precipitates around 60 nm allows their coherency with the matrix, and further induces the R-phase transformation in the matrix. On the other hand, the B2 matrix exhibits a winding and narrow structure with a skeleton of 18.20 mm and a thickness similar to the precipitates. This discontinuous matrix segmented by the Ni4Ti3 network and pores is responsible for the gradual transformation by stalling the martensite propagation.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000584353100001 Publication Date 2020-08-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1044-5803 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.7 Times cited Open Access OpenAccess
Notes ; This work was supported by the National Natural Science Foundation of China under Grant Nos. 51401081 and 51571092, the Natural Science Foundation of Guangdong Province through Key Project under Grant No. 2018B0303110012 and General Project under Grant No. 2017A030313323, and China Scholarship Council (CSC). ; Approved Most recent IF: 4.7; 2020 IF: 2.714
Call Number UA @ admin @ c:irua:173547 Serial 6590
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Author (up) Cautaerts, N.; Delville, R.; Schryvers, D.
Title ALPHABETA: a dedicated open-source tool for calculating TEM stage tilt angles Type A1 Journal article
Year 2019 Publication Journal of microscopy Abbreviated Journal J Microsc-Oxford
Volume 273 Issue 3 Pages 189-198
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000458426100004 Publication Date 2018-12-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2720 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.692 Times cited 2 Open Access Not_Open_Access
Notes ENGIE Ph.D. sponsorship, 2015-AC-007 – BSUEZ6900 ; Approved Most recent IF: 1.692
Call Number EMAT @ emat @UA @ admin @ c:irua:157474 Serial 5163
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Author (up) Cautaerts, N.; Delville, R.; Stergar, E.; Pakarinen, J.; Verwerft, M.; Yang, Y.; Hofer, C.; Schnitzer, R.; Lamm, S.; Felfer, P.; Schryvers, D.
Title The role of Ti and TiC nanoprecipitates in radiation resistant austenitic steel: A nanoscale study Type A1 Journal article
Year 2020 Publication Acta Materialia Abbreviated Journal Acta Mater
Volume 197 Issue Pages 184-197
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract This work encompasses an in-depth transmission electron microscopy and atom probe tomography study of Ti-stabilized austenitic steel irradiated with Fe-ions. The focus is on radiation induced segregation and precipitation, and in particular on how Ti and TiC affect these processes. A 15-15Ti steel (grade: DIN 1.4970) in two thermo-mechanical states (cold-worked and aged) was irradiated at different temperatures up to a dose of 40 dpa. At low irradiation temperatures, the cold-worked and aged materials evolved to a similar microstructure dominated by small Si and Ni clusters, corresponding to segregation to small point defect clusters. TiC precipitates, initially present in the aged material, were found to be unstable under these irradiation conditions. Elevated irradiation temperatures resulted in the nucleation of nanometer sized Cr enriched TiC precipitates surrounded by Si and Ni enriched shells. In addition, nanometer sized Ti- and Mn-enriched G-phase (M6Ni16Si7) precipitates formed, often attached to TiC precipitates. Post irradiation, larger number densities of TiC were observed in the cold-worked material compared to the aged material. This was correlated with a lower volume fraction of G-phase. The findings suggest that at elevated irradiation temperatures, the precipitate-matrix interface is an important point defect sink and contributes to the improved radiation resistance of this material. The study is a first of its kind on stabilized steel and demonstrates the significance of the small Ti addition to the evolution of the microstructure under irradiation. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000564767000001 Publication Date 2020-07-10
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 9.4 Times cited Open Access Not_Open_Access
Notes ; This work was supported by ENGIE [contract number 2015-AC-007 e BSUEZ6900]; the U.S. Department of Energy, Office of Nuclear Energy under DOE Idaho Operations Office Contract DE-AC07051D14517 as part of a Nuclear Science User Facilities experiment; and by the MYRRHA program at SCK-CEN, Belgium. Funding of the Austrian BMK (846933) in the framework of the program “Production of the future” and the “BMK Professorship for Industry” is gratefully acknowledged. We want to thank the staffat MIBL for assisting with the ion irradiations as well as the staffat CAES for assisting with FIB work and conducting APT measurements. ; Approved Most recent IF: 9.4; 2020 IF: 5.301
Call Number UA @ admin @ c:irua:171956 Serial 6626
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Author (up) Cautaerts, N.; Delville, R.; Stergar, E.; Schryvers, D.; Verwerft, M.
Title Tailoring the Ti-C nanoprecipitate population and microstructure of titanium stabilized austenitic steels Type A1 Journal article
Year 2018 Publication Journal of nuclear materials Abbreviated Journal J Nucl Mater
Volume 507 Issue 507 Pages 177-187
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The present work reports on the microstructural evolution of a new heat of 24% cold worked austenitic DIN 1.4970 (15-15Ti) nuclear cladding steel subjected to ageing heat treatments of varying duration between 500 and 800 degrees C (by steps of 100 degrees C). The primary aim was studying the finely dispersed Ti-C nanoprecipitate population, which are thought to be beneficial for creep and swelling resistance during service. Their size distribution and number density were estimated through dark field imaging and bright field Moire imaging techniques in the transmission electron microscope. Nanoprecipitates formed at and above 600 degrees C, which is a lower temperature than previously reported. The observed nucleation, growth and coarsening behavior of the nanoprecipitates were consistent with simple diffusion arguments. The formation of nanoprecipitates coincided with significant dissociation of dislocations as evidenced by weak beam dark field imaging. Possible mechanisms, including Silcock's stacking fault growth model and Suzuki segregation, are discussed. Recrystallization observed after extended ageing at 800 degrees C caused the redissolution of nanoprecipitates. Large primary Ti(C,N) and (Ti,Mo)C precipitates that occur in the as-received material, and M23C6 precipitates that nucleate on grain boundaries at low temperatures were also characterized by a selective dissolution procedure involving filtration, X-ray diffraction and quantitative Rietveld refinement. The partitioning of key elements between the different phases was derived by combining these findings and was consistent with thermodynamic considerations and the processing history of the steel. (C) 2018 Elsevier B.V. All rights reserved.
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Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000438019800021 Publication Date 2018-04-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3115 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.048 Times cited 1 Open Access Not_Open_Access
Notes ; We would like to acknowledge ENGIE, SCK.CEN, the SCK.CEN academy and the MYRRHA project for the financial support of this work. Special thanks to T. Wangle and P. Dries for their help with filtration and gravimetry. Also thanks to Dr. G. Leinders for the discussions on XRD and Rietveld refinement. Thanks to E. Charalampopoulou and A. Youssef for assisting with the dissolution experiments. ; Approved Most recent IF: 2.048
Call Number UA @ lucian @ c:irua:152382 Serial 5043
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Author (up) Cautaerts, N.; Delville, R.; Stergar, E.; Schryvers, D.; Verwerft, M.
Title Characterization of (Ti,Mo,Cr)C nanoprecipitates in an austenitic stainless steel on the atomic scale Type A1 Journal article
Year 2019 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 164 Issue Pages 90-98
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Nanometer sized (Ti,Mo,Cr)C (MX-type) precipitates that grew in a 24% cold worked Ti-stabilized austenitic stainless steel (grade DIN 1.4970, member of the 15-15Ti austenitic stainless steels) after heat treatment were fully characterized with transmission electron microscopy (TEM), probe corrected high angle annular dark field scanning transmission electron microscopy (HR-HAADF STEM), and atom probe tomography (APT). The precipitates shared the cube-on-cube orientation with the matrix and were facetted on {111} planes, yielding octahedral and elongated octahedral shapes. The misfit dislocations were believed to have Burgers vectors a/6<112> which was verified by geometrical phase analysis (GPA) strain mapping of a matrix-precipitate interface. The dislocations were spaced five to seven atomic

planes apart, on average slightly wider than expected for the lattice parameters of steel and TiC. Quantitative atom probe tomography analysis of the precipitates showed that precipitates were significantly enriched in Mo, Cr and V, and that they were hypostoichiometric with respect to C. These findings were consistent with a reduced lattice parameter. The precipitates were found primarily on Shockley

partial dislocations originating from the original perfect dislocation network. These novel findings could contribute to the understanding of how TiC nanoprecipitates interact with point defects and matrix dislocations. This is essential for the application of these Ti-stabilized steels in high temperature environments or fast spectrum nuclear fission reactors.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000456902800008 Publication Date 2018-10-11
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 2 Open Access Not_Open_Access: Available from 12.10.2020
Notes This work was supported by ENGIE [contract number 2015-AC- 007 e BSUEZ6900]; the U.S. Department of Energy, Office of Nuclear Energy under DOE Idaho Operations Office Contract DE-AC07- 051D14517 as part of a Nuclear Science User Facilities experiment; and by the MYRRHA program in development at SCKCEN, Belgium. Special thanks to Dr. H. Mezerji and Dr. T. Altantzis for the work on the FEI Titan microscope.We also want to thank Ms. J. Burns for the help on the FIB and Dr. Y. Wu at CAES for conducting the APT measurements. Approved Most recent IF: 5.301
Call Number EMAT @ emat @c:irua:154873UA @ admin @ c:irua:154873 Serial 5060
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Author (up) Cautaerts, N.; Lamm, S.; Stergar, E.; Pakarinen, J.; Yang, Y.; Hofer, C.; Schnitzer, R.; Felfer, P.; Verwerft, M.; Delville, R.; Schryvers, D.
Title Atom probe tomography data collection from DIN 1.4970 (15-15Ti) austenitic stainless steel irradiated with Fe ions Type Dataset
Year 2020 Publication Abbreviated Journal
Volume Issue Pages
Keywords Dataset; Electron microscopy for materials research (EMAT)
Abstract This dataset comprises a large collection of atom probe tomography datasets collected from DIN 1.4970 alloy that was irradiated with Fe ions at different conditions. The DIN 1.4970 alloy is an austenitic stainless steel with 15 wt% Cr, 15 wt% Ni, a small addition of Ti. The full composition and characterization of our material can be found published elsewhere [1,2]. Some of our material was subjected to ageing heat treatments at different temperatures for different times. Small samples of our original material and aged material was irradiated at the Michigan Ion Beam Laboratory in 2017 with 4.5 MeV Fe ions up to 40 dpa at an average dose rate of 2×10−4 dpa/s. This was done at three different temperatures: 300, 450, and 600 ºC. Atom probe samples were made of the irradiated layers (approximately 1.5 micron deep) with focused ion beam and mounted on Microtip coupons. APT measurements took place on three CAMECA LEAP-HR systems located at CAES in Idaho Falls, USA (files beginning with R33), at Montanuniversität Leoben in Leoben, Austria (R21) and at Friedrich–Alexander University in Erlangen, Germany (R56).
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access Not_Open_Access
Notes ; ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:169127 Serial 6454
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Author (up) Chandrasekaran, M.; Ghosh, G.; Schryvers, D.; de Graef, M.; Delaey, L.; Van Tendeloo, G.
Title Decomposition of a metastable bcc phase in rapidly solidified Ni-9 at.% Zr and Ni-8 at.%X alloys Type A1 Journal article
Year 1997 Publication Philosophical magazine: A: physics of condensed matter: defects and mechanical properties Abbreviated Journal Philos Mag A
Volume 75 Issue Pages 677-701
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1997WN48000006 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0141-8610; 1364-2804 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 5 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:21343 Serial 608
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Author (up) Charalampopoulou, E.; Cautaerts, N.; Van der Donck, T.; Schryvers, D.; Lambrinou, K.; Delville, R.
Title Orientation relationship of the austenite-to-ferrite transformation in austenitic stainless steels due to dissolution corrosion in contact with liquid Pb-Bi eutectic Type A1 Journal article
Year 2019 Publication Scripta materialia Abbreviated Journal Scripta Mater
Volume 167 Issue 167 Pages 66-70
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The orientation relationship of an austenite-to-ferrite phase transformation in 316L stainless steels induced by the loss of austenite stabilizers resulting from the steel dissolution corrosion in liquid Pb-Bi eutectic was studied by means of electron backscatter diffraction. The misorientations at the austenite/ferrite interface were compared to the prevailing orientation relationship models in steels. The Pitsch orientation relationship model was found to be predominant, which is unusual for austenite-to-ferrite bulk transformations in steels. The nature of this particular transformation, which involves loss of steel alloying elements and the presence of an interfacial liquid metal layer, is discussed to explain this finding. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000468720000014 Publication Date 2019-04-06
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 3 Open Access Not_Open_Access
Notes ; The authors would like to thank J. Joris (SCK center dot CEN) for technical support during corrosion testing, J. Lim (SCK center dot CEN) for the manufacture and calibration of the oxygen sensors used in this work and W. Van Renterghem (SCK center dot CEN) for his valuable help with the EBSD measurements. The steel suppliers were: Industeel, ArcelorMittal Group, for the 316L-SA plate, and Panchmahal Steel Ltd., India, for the 316L-CWrod. The authors gratefully acknowledge the financial support provided within the framework of the ongoing development of the MYRRHA irradiation facility. The research leading to these results falls within the framework of the European Energy Research Alliance Joint Programme on Nuclear Materials (EERA JPNM). ; Approved Most recent IF: 3.747
Call Number UA @ admin @ c:irua:160228 Serial 5257
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Author (up) Charalampopoulou, E.; Delville, R.; Verwerft, M.; Lambrinou, K.; Schryvers, D.
Title Transmission electron microscopy study of complex oxide scales on DIN 1.4970 steel exposed to liquid Pb-Bi eutectic Type A1 Journal article
Year 2019 Publication Corrosion science Abbreviated Journal Corrosion Science
Volume 147 Issue Pages 22-31
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The deployment of Gen-IV lead-cooled fast reactors requires a good compatibility between the selected structural/cladding steels and the inherently corrosive heavy liquid metal coolant. An effective liquid metal corrosion mitigation strategy involves the in-situ steel passivation in contact with the oxygen-containing Pb-alloy coolant. Transmission electron microscopy was used in this work to study the multi-layered oxide scales forming on an austenitic stainless steel fuel cladding exposed to oxygen-containing (CO ≈ 10−6 mass%) static liquid leadbismuth eutectic (LBE) for 1000 h between 400 and 500 °C. The oxide scale constituents were analyzed, including the intertwined phases comprising the innermost biphasic layer.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000456902100003 Publication Date 2018-10-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0010938X ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 5 Open Access OpenAccess
Notes The authors would like to thank J. Joris for the technical support during corrosion testing and J. Lim for the manufacturing and calibration of the oxygen sensors and oxygen pumps used in this work. E. Charalampopoulou personally thanks H. Heidari, S. Pourbabak, A. Orekhov (EMAT) and N. Cautaerts (EMAT, SCK•CEN), for their valuable help with the training of the FEI Tecnai Osiris S/TEM and Jeol 3000 S/ TEM, respectively, as well as S. Van den Broeck (EMAT), J. Pakarinen (SCK•CEN) and W. Van Renterghem (SCK•CEN) for FIB sample preparation. Moreover, the authors gratefully acknowledge the funding provided in the framework of the ongoing development of the MYRRHA irradiation facility. The research leading to these results falls within the framework of the European Energy Research Alliance Joint Programme on Nuclear Materials (EERA JPNM). Approved Most recent IF: NA
Call Number EMAT @ emat @UA @ admin @ c:irua:157541 Serial 5164
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Author (up) Charalampopoulou, E.; Lambrinou, K.; Van der Donck, T.; Paladino, B.; Di Fonzo, F.; Azina, C.; Eklund, P.; Mraz, S.; Schneider, J.M.; Schryvers, D.; Delville, R.
Title Early stages of dissolution corrosion in 316L and DIN 1.4970 austenitic stainless steels with and without anticorrosion coatings in static liquid lead-bismuth eutectic (LBE) at 500 degrees C Type A1 Journal article
Year 2021 Publication Materials Characterization Abbreviated Journal Mater Charact
Volume 178 Issue Pages 111234
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract This work addresses the early stages (<= 1000 h) of the dissolution corrosion behavior of 316L and DIN 1.4970 austenitic stainless steels in contact with oxygen-poor (C-O < 10(-8) mass%), static liquid lead-bismuth eutectic (LBE) at 500 degrees C for 600-1000 h. The objective of this study was to determine the relative early-stage resistance of the uncoated steels to dissolution corrosion and to assess the protectiveness of select candidate coatings (Cr2AlC, Al2O3, V2AlxCy). The simultaneous exposure of steels with intended differences in microstructure and thermomechanical state showed the effects of steel grain size, density of annealing/deformation twins, and secondary precipitates on the steel dissolution corrosion behavior. The findings of this study provide recommendations on steel manufacturing with the aim of using the steels to construct Gen-IV lead-cooled fast reactors.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000752582700001 Publication Date 2021-06-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1044-5803 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.714 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 2.714
Call Number UA @ admin @ c:irua:186509 Serial 7061
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Author (up) Chen, X.; Cao, S.; Ikeda, T.; Srivastava, V.; Snyder, G.J.; Schryvers, D.; James, R.D.
Title A weak compatibility condition for precipitation with application to the microstructure of PbTe-Sb2Te3 thermoelectrics Type A1 Journal article
Year 2011 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 59 Issue 15 Pages 6124-6132
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract We propose a weak condition of compatibility between phases applicable to cases exhibiting full or partial coherence and Widmanstätten microstructure. The condition is applied to the study of Sb2Te3 precipitates in a PbTe matrix in a thermoelectric alloy. The weak condition of compatibility predicts elongated precipitates lying on a cone determined by a transformation stretch tensor. Comparison of this cone with the long directions of precipitates determined by a slice-and-view method of scanning electron microscopy combined with focused ion beam sectioning shows good agreement between theory and experiment. A further study of the morphology of precipitates by the Eshelby method suggests that interfacial energy also plays a role and gives an approximate value of interfacial energy per unit area of 250 dyn cm−1.
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Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000294086900026 Publication Date 2011-07-22
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 8 Open Access
Notes Approved Most recent IF: 5.301; 2011 IF: 3.755
Call Number UA @ lucian @ c:irua:92388 Serial 3911
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Author (up) Chen, Z.; Tan, Z.; Ji, G.; Schryvers, D.; Ouyang, Q.; Li, Z.
Title Effect of interface evolution on thermal conductivity of vacuum hot pressed SiC/Al composites Type A1 Journal article
Year 2015 Publication Advanced engineering materials Abbreviated Journal Adv Eng Mater
Volume 17 Issue 17 Pages 1076-1084
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The SiC/Al composites have been fabricated by a vacuum hot pressing (VHP) process in order to study the effect of interface evolution on the global thermal conductivity (TC). By optimizing the VHP parameters of sintering temperature and time, the three different kinds of SiC/Al interface configurations, that is, non-bonded, diffusion-bonded, and reaction-bonded interfaces, are formed and identified by measurement of relative density, X-ray diffraction, scanning and (high-resolution) transmission electron microscopy. The VHPed composite sintered at 655 °C for 60 min is fully dense and presents a tightly-adhered and clean SiC/Al interface at the nanoscale, the ideal diffusion-bonded interface being the most favorable for minimizing interfacial thermal resistance, which in turn results in the highest TC of around 270 W/mK.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000357680700019 Publication Date 2015-01-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1438-1656; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.319 Times cited 9 Open Access
Notes Approved Most recent IF: 2.319; 2015 IF: 1.758
Call Number c:irua:123000 Serial 818
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Author (up) Coghe, F.; Tirry, W.; Rabet, L.; Schryvers, D.; Van Houtte, P.
Title Importance of twinning in static and dynamic compression of a Ti-6Al-4V titanium alloy with an equiaxed microstructure Type A1 Journal article
Year 2012 Publication Materials science and engineering: part A: structural materials: properties, microstructure and processing Abbreviated Journal Mat Sci Eng A-Struct
Volume 537 Issue Pages 1-10
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Whereas deformation twinning is known to be an important deformation mechanism for hexagonal materials like magnesium and pure titanium, so far almost no literature exists on the twinning behaviour of the Ti-6Al-4V alloy. In this work it was shown that the activation of twinning as a deformation mechanism could have a pronounced effect on the mechanical behaviour of the Ti-6Al-4V alloy. This effect is even more pronounced under dynamic loading conditions. Transmission electron microscopy showed that only the {1 0 1 2}{1 0 1 1} tensile twin system was activated under certain loading conditions. Light-optical microscopy and electron backscatter diffraction data were afterwards used to experimentally determine the twin fractions. The importance of twinning for the texture evolution was also studied. It was shown that even small twin fractions can lead to distinct texture features, especially due to the discrete reorientation of the c-axes. The experimental results were compared to simulated results that were obtained with a viscoplastic self-consistent crystal plasticity code, after experimental validation that twinning can be reliably modelled as a unidirectional slip system. Although good agreement was obtained for the experimental and simulated stress-strain curves, the simulated results concerning twinning correlated well only on a qualitative basis as the simulated twin fractions were systematically higher than the experimental fractions. This seems to strengthen the hypothesis made by other research groups that complete grains might reorient by twinning. (C) 2011 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000301473300001 Publication Date 2011-12-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-5093; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.094 Times cited 35 Open Access
Notes Approved Most recent IF: 3.094; 2012 IF: 2.108
Call Number UA @ lucian @ c:irua:97818 Serial 1565
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Author (up) Colla, M.-S.; Amin-Ahmadi, B.; Idrissi, H.; Malet, L.; Godet, S.; Raskin, J.-P.; Schryvers, D.; Pardoen, T.
Title Dislocation-mediated relaxation in nanograined columnar ​palladium films revealed by on-chip time-resolved HRTEM testing Type A1 Journal article
Year 2015 Publication Nature communications Abbreviated Journal Nat Commun
Volume 6 Issue 6 Pages 5922
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The high-rate sensitivity of nanostructured metallic materials demonstrated in the recent literature is related to the predominance of thermally activated deformation mechanisms favoured by a large density of internal interfaces. Here we report time-resolved high-resolution electron transmission microscopy creep tests on thin nanograined films using on-chip nanomechanical testing. Tests are performed on ​palladium, which exhibited unexpectedly large creep rates at room temperature. Despite the small 30-nm grain size, relaxation is found to be mediated by dislocation mechanisms. The dislocations interact with the growth nanotwins present in the grains, leading to a loss of coherency of twin boundaries. The density of stored dislocations first increases with applied deformation, and then decreases with time to drive additional deformation while no grain boundary mechanism is observed. This fast relaxation constitutes a key issue in the development of various micro- and nanotechnologies such as ​palladium membranes for hydrogen applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000348742300002 Publication Date 2015-01-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 34 Open Access
Notes Iap7/21; Fwo G012012n Approved Most recent IF: 12.124; 2015 IF: 11.470
Call Number c:irua:122045 Serial 731
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Author (up) Colla, M.-S.; Wang, B.; Idrissi, H.; Schryvers, D.; Raskin, J.-P.; Pardoen, T.
Title High strength-ductility of thin nanocrystalline palladium films with nanoscale twins : on-chip testing and grain aggregate model Type A1 Journal article
Year 2012 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 60 Issue 4 Pages 1795-1806
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The mechanical behaviour of thin nanocrystalline palladium films with an ∼30 nm in plane grain size has been characterized on chip under uniaxial tension. The films exhibit a large strain hardening capacity and a significant increase in the strength with decreasing thickness. Transmission electron microscopy has revealed the presence of a moderate density of growth nanotwins interacting with dislocations. A semi-analytical grain aggregate model is proposed to investigate the impact of different contributions to the flow behaviour, involving the effect of twins, of grain size and of the presence of a thin surface layer. This model provides guidelines to optimizing the strength/ductility ratio of the films.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000301989500035 Publication Date 2012-02-02
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 38 Open Access
Notes Iap Approved Most recent IF: 5.301; 2012 IF: 3.941
Call Number UA @ lucian @ c:irua:94213 Serial 1465
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Author (up) Delmelle, R.; Amin-Ahmadi, B.; Sinnaeve, M.; Idrissi, H.; Pardoen, T.; Schryvers, D.; Proost, J.
Title Effect of structural defects on the hydriding kinetics of nanocrystalline Pd thin films Type A1 Journal article
Year 2015 Publication International journal of hydrogen energy Abbreviated Journal Int J Hydrogen Energ
Volume 40 Issue 40 Pages 7335-7347
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract While the microstructure of a metal is well-known to affect its equilibrium hydrogen uptake and therefore the hydriding thermodynamics, microstructural effects on the hydriding kinetics are much less documented. Moreover, for thin film systems, such microstructural effects are difficult to separate from the internal stress effect, since most defects generate internal stresses. Such a decoupling has been achieved in this paper for nanocrystalline Pd thin film model systems through the use of a high-resolution, in-situ curvature measurement set-up during Pd deposition, annealing and hydriding. This set-up allowed producing Pd thin films with similar internal stress levels but significantly different microstructures. This was evidenced from detailed defect statistics obtained by transmission electron microscopy, which showed that the densities of grain boundaries, dislocations and twin boundaries have all been lowered by annealing. The same set-up was then used to study the hydriding equilibrium and kinetic behaviour of the resulting films at room temperature. A full quantitative analysis of their hydriding cycles showed that the rate constants of both the adsorption- and absorption-limited kinetic regimes were strongly affected by microstructure. Defect engineering was thereby shown to increase the rate constants for hydrogen adsorption and absorption in Pd by a factor 40 and 30, respectively. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000355884300012 Publication Date 2015-05-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0360-3199; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.582 Times cited 13 Open Access
Notes Iap 7/21 Approved Most recent IF: 3.582; 2015 IF: 3.313
Call Number c:irua:126429 Serial 838
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Author (up) Delville, R.; James, R.D.; Salman, U.; Finel, A.; Schryvers, D.
Title Transmission electron microscopy study of low-hysteresis shape memory alloys Type P1 Proceeding
Year 2009 Publication Abbreviated Journal
Volume Issue Pages 02005,1-02005,7
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract Recent findings have linked low hysteresis in shape memory alloys with phase compatibility between austenite and martensite. In order to investigate the evolution of microstructure as the phase compatibility increases and the hysteresis is reduced, transmission electron microscopy was used to study the alloy system Ti50Ni50-xPdx where the composition is systemically tuned to approach perfect compatibility. Changes in morphology, twinning density and twinning modes are reported along with special microstructures occurring when the compatibility is achieved. In addition, the interface between austenite and a single variant of martensite was studied by high-resolution and conventional electron microscopy. The atomically sharp, defect free, low energy configuration of the interface suggests that it plays an important role in the lowering of hysteresis. Finally, dynamical modeling of the martensitic transformation using the phase-field micro-elasticity model within the geometrically linear theory succeeded in reproducing the change in microstructure as the compatibility condition is satisfied. Latest results on the extension of these findings in other Ni-Ti based ternary/quaternary systems are also reported.
Address
Corporate Author Thesis
Publisher Edp Place of Publication Coutaboeuf Editor
Language Wos 000274582300009 Publication Date 2009-08-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:81951 Serial 3716
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Author (up) Delville, R.; Kasinathan, S.; Zhang, Z.; van Humbeeck, J.; James, R.D.; Schryvers, D.
Title Transmission electron microscopy study of phase compatibility in low hysteresis shape memory alloys Type A1 Journal article
Year 2010 Publication Philosophical magazine Abbreviated Journal Philos Mag
Volume 90 Issue 1/4 Pages 177-195
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Recent findings have linked low hysteresis in shape memory alloys with phase compatibility between austenite and martensite. To investigate the evolution of microstructure as phase compatibility increases and hysteresis is reduced, transmission electron microscopy was used to study the alloy system Ti50Ni50xPdx, where the composition is systemically tuned to approach perfect compatibility. Changes in morphology, twinning density and twinning modes are reported, along with special microstructures occurring when compatibility is achieved. In addition, the interface between austenite and a single variant of martensite was studied by high-resolution and conventional electron microscopy. The low energy configuration of the interface detailed in this article suggests that it plays an important role in the lowering of hysteresis compared to classical habit plane interfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000274576500013 Publication Date 2010-01-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1478-6435;1478-6443; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.505 Times cited 70 Open Access
Notes Multimat; FWO Approved Most recent IF: 1.505; 2010 IF: 1.304
Call Number UA @ lucian @ c:irua:79859 Serial 3718
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Author (up) Delville, R.; Malard, B.; Pilch, J.; Schryvers, D.
Title Microstructure changes during non-conventional heat treatment of thin NiTi wires by pulsed electric current studied by transmission electron microscopy Type A1 Journal article
Year 2010 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 58 Issue 13 Pages 4503-4515
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Transmission electron microscopy, electrical resistivity measurements and mechanical testing were employed to investigate the evolution of microstructure and functional superelastic properties of 0.1 mm diameter as-drawn NiTi wires subjected to a non-conventional heat treatment by controlled electric pulse currents. This method enables a better control of the recovery and recrystallization processes taking place during the heat treatment and accordingly a better control on the final microstructure. Using a stepwise approach of millisecond pulse annealing, it is shown how the microstructure evolves from a severely deformed state with no functional properties to an optimal nanograined microstructure (2050 nm) that is partially recovered through polygonization and partially recrystallized and that has the best functional properties. Such a microstructure is highly resistant against dislocation slip upon cycling, while microstructures annealed for longer times and showing mostly recrystallized grains were prone to dislocation slip, particularly as the grain size exceeds 200 nm.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000279787100020 Publication Date 2010-06-02
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 110 Open Access
Notes Multimat; FWO IAA Approved Most recent IF: 5.301; 2010 IF: 3.791
Call Number UA @ lucian @ c:irua:83279 Serial 2062
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Author (up) Delville, R.; Malard, B.; Pilch, J.; Sittner, P.; Schryvers, D.
Title Transmission electron microscopy investigation of dislocation slip during superelastic cycling of NiTi wires Type A1 Journal article
Year 2011 Publication International journal of plasticity Abbreviated Journal Int J Plasticity
Volume 27 Issue 2 Pages 282-297
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Superelastic deformation of thin NiTi wires containing various nanograined microstructures was investigated by tensile cyclic loading with in situ evaluation of electric resistivity. Defects created by the superelastic cycling in these wires were analyzed by transmission electron microscopy. The role of dislocation slip in superelastic deformation is discussed. NiTi wires having finest microstructures (grain diameter <100 nm) are highly resistant against dislocation slip, while those with fully recrystallized microstructure and grain size exceeding 200 nm are prone to dislocation slip. The density of the observed dislocation defects increases significantly with increasing grain size. The upper plateau stress of the superelastic stressstrain curves is largely grain size independent from 10 up to 1000 nm. It is hence claimed that the HallPetch relationship fails for the stress-induced martensitic transformation in this grain size range. It is proposed that dislocation slip taking place during superelastic cycling is responsible for the accumulated irreversible strains, cyclic instability and degradation of functional properties. No residual martensite phase was found in the microstructures of superelastically cycled wires by TEM and results of the in situ electric resistance measurements during straining also indirectly suggest that none or very little martensite phase remains in the studied cycled superelastic wires after unloading. The accumulation of dislocation defects, however, does not prevent the superelasticity. It only affects the shape of the stressstrain response, makes it unstable upon cycling and changes the deformation mode from localized to homogeneous. The activity of dislocation slip during superelastic deformation of NiTi increases with increasing test temperature and ultimately destroys the superelasticity as the plateau stress approaches the yield stress for slip. Deformation twins in the austenite phase ({1 1 4} compound twins) were frequently found in cycled wires having largest grain size. It is proposed that they formed in the highly deformed B19′ martensite phase during forward loading and are retained in austenite after unloading. Such twinning would represent an additional deformation mechanism of NiTi yielding residual irrecoverable strains.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000284921800007 Publication Date 2010-05-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0749-6419; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.702 Times cited 157 Open Access
Notes Fwo; Iap Approved Most recent IF: 5.702; 2011 IF: 4.603
Call Number UA @ lucian @ c:irua:84651 Serial 3709
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Author (up) Delville, R.; Malard, B.; Pilch, J.; Sittner, P.; Schryvers, D.
Title Transmission electron microscopy study of microstructural evolution in nanograined Ni-Ti microwires heat treated by electric pulse Type A1 Journal article
Year 2011 Publication Diffusion and defect data : solid state data : part B : solid state phenomena Abbreviated Journal
Volume 172/174 Issue Pages 682-687
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Transmission electron microscopy and mechanical testing were employed to investigate the evolution of microstructure and functional superelastic properties of 0.1mm diameter as-drawn Ni-Ti wires subjected to a non-conventional heat treatment by controlled electric pulse current. This method enables a finer control of the recovery and recrystallisation processes taking place during the heat treatment and accordingly a better control on the final microstructure. The best functional properties were obtained for heat-treated Ni-Ti wires having a nanograined microstructure (20-50 nm) partially recovered through polygonization and partially recrystallized. Such microstructure is highly resistant against dislocation slip upon cycling, while microstructures annealed for longer time and showing mostly recrystallized grains were prone to dislocation slip, particularly as the grain size exceeds 100 nm. The density of dislocation defects increased significantly with increasing grain size of the microstructure. The activity of three <100>/{011} slip systems was identified in the largest grains of 500-1200 nm. An additional mode of plastic deformation, {114} compound austenite twinning, was observed in the largest grains of fully recrystallized microstructures. It is proposed that dislocation slip (and possibly deformation twinning) occurring in superelastic cycling is coupled with the stress-induced martensitic transformation.
Address
Corporate Author Thesis
Publisher Place of Publication Vaduz Editor
Language Wos 000303359700105 Publication Date 2011-07-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1662-9779; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:90154 Serial 3717
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Author (up) Delville, R.; Schryvers, D.
Title Transmission electron microscopy study of combined precipitation of Ti2Ni(Pd) and Ti2Pd(Ni) in a Ti50Ni30Pd20 alloy Type A1 Journal article
Year 2010 Publication Intermetallics Abbreviated Journal Intermetallics
Volume 18 Issue 12 Pages 2353-2360
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report a new mode of precipitation in a B19 martensitic Ti50Ni30Pd20 shape memory alloy consisting of a central Ti2Ni(Pd) precipitate surrounded by an austenite area containing Ti2Pd(Ni) precipitates. The morphology and crystallography of the precipitation area is investigated using conventional and high resolution electron microscopy. In particular, the orientation relationship and the coherency strain between the Ti2Pd(Ni) precipitate and the surrounding retained B2 matrix are discussed. A study of local composition in relation with a ternary phase diagram using X-ray energy dispersive spectroscopy with a nanoprobe gives evidences of the formation mechanism.
Address
Corporate Author Thesis
Publisher Place of Publication Chicago, Ill. Editor
Language Wos 000284447500014 Publication Date 2010-09-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0966-9795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.14 Times cited 9 Open Access
Notes Multimat; Iap Approved Most recent IF: 3.14; 2010 IF: 2.335
Call Number UA @ lucian @ c:irua:84473 Serial 3714
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Author (up) Delville, R.; Schryvers, D.; Zhang, Z.; James, R.D.
Title Transmission electron microscopy investigation of microstructures in low-hysteresis alloys with special lattice parameters Type A1 Journal article
Year 2009 Publication Scripta materialia Abbreviated Journal Scripta Mater
Volume 60 Issue 5 Pages 293-296
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A sharp drop in hysteresis is observed for shape memory alloys satisfying the compatibility condition between austenite and martensite, i.e. ë2 = 1, where ë2 is the middle eigenvalue of the transformation strain matrix. The present work investigates the evolution of microstructure by transmission electron microscopy as the composition of the Ti50Ni50−xPdx system is systemically tuned to achieve the condition ë2 = 1. Changes in morphology, twinning density and twinning modes are reported along with twinless martensite and exact austenitemartensite interfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000262553300007 Publication Date 2008-11-08
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 56 Open Access
Notes Multimat Approved Most recent IF: 3.747; 2009 IF: 2.949
Call Number UA @ lucian @ c:irua:76017 Serial 3710
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Author (up) Delville, R.; Shi, H.; James, R.D.; Schryvers, D.
Title Special microstructures and twin features in Ti50Ni50-x(Pd,Au)x at small hysteresis Type A1 Journal article
Year 2011 Publication Diffusion and defect data : solid state data : part B : solid state phenomena Abbreviated Journal
Volume 172/174 Issue Pages 105-110
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The breaking of symmetry due to atomic displacements in the austenite-martensite phase transformation generally leads to their crystallographic incompatibility. Energy minimizing accommodation mechanisms such as martensite twinning have been recently shown to be a source of hysteresis and irreversible plastic deformation. Compatibility between the two phases can however be achieved by carefully tuning lattice parameters through composition change. A dramatic drop in hysteresis and novel microstructures such as a lowering of the amount of twin lamella are then observed. Related theoretical and simulation works also support the existence of such microstructures including peculiar self-accommodating configurations at near-compatibility. We present the transmission electron microscopy (TEM) study of these novel microstructures for the alloy systems Ti50Ni50-xPdx and Ti50Ni50-xAux where the composition was systemically tuned to approach perfect compatibility. High resolution imaging of the interface between austenite and martensite supplies evidences of compatibility at the atomic level.
Address
Corporate Author Thesis
Publisher Place of Publication Vaduz Editor
Language Wos 000303359700016 Publication Date 2011-07-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1662-9779; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:90155 Serial 3069
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Author (up) Ding, L.; Orekhov, A.; Weng, Y.; Jia, Z.; Idrissi, H.; Schryvers, D.; Muraishi, S.; Hao, L.; Liu, Q.
Title Study of the Q′ (Q)-phase precipitation in Al–Mg–Si–Cu alloys by quantification of atomic-resolution transmission electron microscopy images and atom probe tomography Type A1 Journal article
Year 2019 Publication Journal of materials science Abbreviated Journal J Mater Sci
Volume 54 Issue 10 Pages 7943-7952
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The precipitation mechanism of the Q phase in Al-Mg-Si-Cu alloys has long been the subject of ambiguity and debate since its metastable phase (Q 0) has the same crystal structure and similar lattice parameters as its equilibrium counterparts. In the present work, the evolution of the Q 0 (Q) phase during aging is studied by combination of quantitative atomic-resolution scanning transmission electron microscopy and atom probe tomography. It was found that the transformation from the Q 0 to the Q phase involves changes of the occupancy of Al atoms in atomic columns of the Q 0 (Q) phase. The Al atoms incorporated in the Cu, Si and Mg columns are gradually released into the Al matrix, while mixing between Cu and Si atoms occurs in the Si columns. This transformation process is mainly attributed to the low lattice misfit of the equilibrium Q phase. Besides, the formation of various compositions of the Q phase is due to the different occupancy in the atomic columns of the Q phase. The occupancy changes in the columns of the Q phase are kinetically controlled and are strongly influenced by the alloy composition and aging temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000460069500043 Publication Date 2019-02-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2461 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.599 Times cited 1 Open Access Not_Open_Access
Notes Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing, cstc2017zdcy-zdzxX0006 ; Fundamental Research Funds for the Central Universities of China, 2018CDGFCL0002 106112017CDJQJ308822 ; Belgian National Fund for Scientific Research; the National Natural Science Foundation of China, 51871035 ; This work was supported by the Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing (Grant No. cstc2017zdcyzdzxX0006), the Fundamental Research Funds for the Central Universities of China (Grant No. 2018CDGFCL0002), the National Natural Science Foundation of China (Grant No. 51871035) and the Foundation for Innovative Research Groups J Mater Sci National Natural Science Foundation of China (Grant No. 51421001). H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). Approved Most recent IF: 2.599
Call Number EMAT @ emat @UA @ admin @ c:irua:158112 Serial 5158
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Author (up) Ding, L.; Raskin, J.-P.; Lumbeeck, G.; Schryvers, D.; Idrissi, H.
Title TEM investigation of the role of the polycrystalline-silicon film/substrate interface in high quality radio frequency silicon substrates Type A1 Journal article
Year 2020 Publication Materials Characterization Abbreviated Journal Mater Charact
Volume 161 Issue Pages 110174-10
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The microstructural characteristics of two polycrystalline silicon (poly-Si) films with different electrical properties produced by low-pressure chemical vapour deposition on top of high resistivity silicon substrates were investigated by advanced transmission electron microscopy (TEM), including high resolution aberration corrected TEM and automated crystallographic orientation mapping in TEM. The results reveal that the nature of the poly-Si film/Si substrate interface is the main factor controlling the electrical resistivity of the poly-Si films. The high resistivity and high electrical linearity of poly-Si films are strongly promoted by the Sigma 3 twin type character of the poly-Si/Si substrate interface, leading to the generation of a huge amount of extended defects including stacking faults, Sigma 3 twin boundaries as well as Sigma 9 grain boundaries at this interface. Furthermore, a high density of interfacial dislocations has been observed at numerous common and more exotic grain boundaries deviating from their standard crystallographic planes. In contrast, poly-Si film/Si substrate interfaces with random character do not favour the formation of such complex patterns of defects, leading to poor electrical resistivity of the poly-Si film. This finding opens windows for the development of high resistivity silicon substrates for Radio Frequency (RF) integrated circuits (ICs) applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000521515800027 Publication Date 2020-01-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1044-5803 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.7 Times cited Open Access Not_Open_Access
Notes ; H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). ; Approved Most recent IF: 4.7; 2020 IF: 2.714
Call Number UA @ admin @ c:irua:168664 Serial 6621
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Author (up) Ding, L.; Sapanathan, T.; Schryvers, D.; Simar, A.; Idrissi, H.
Title On the formation of antiphase boundaries in Fe₄Al₁₃ intermetallics during a high temperature treatment Type A1 Journal article
Year 2022 Publication Scripta materialia Abbreviated Journal Scripta Mater
Volume 215 Issue Pages 114726-6
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In this paper, we report atomic scale observations and formation mechanisms of a high-density of antiphase boundaries (APBs) within an ultra-fine-grained Fe4Al13 intermetallic layer at an Al/steel interface after a heat treatment at 596 degrees C. The results reveal that the APBs are formed by nucleation and the glide of partial dislocations with Burgers vector of b/3[010] (b = 12.47 angstrom). The intensive activation of APBs locally transforms the Fe4Al13 structure from the quasicrystal approximant structure to a quasicrystal. Very few stacking faults and nanotwins are observed indicating that the formation of planar defects is mainly driven by this transformation. This new insight on the formation of high density of APBs could possibly lead to an improvement in toughness by increasing the strength/ductility balance of this intermetallic.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000800016600003 Publication Date 2022-04-08
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
Call Number UA @ admin @ c:irua:188644 Serial 7088
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Author (up) Ding, L.; Zhao, L.; Weng, Y.; Schryvers, D.; Liu, Q.; Idrissi, H.
Title Atomic-scale investigation of the heterogeneous precipitation in the E (Al₁₈Mg₃Cr₂) dispersoid of 7075 aluminum alloy Type A1 Journal article
Year 2021 Publication Journal Of Alloys And Compounds Abbreviated Journal J Alloy Compd
Volume 851 Issue Pages 156890
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The heterogeneous precipitation of the eta (MgZn2) phase on the E (Al18Mg3Cr2) dispersoids of the 7075 aluminum alloy was systematically investigated by atomic resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and energy dispersive X-ray spectrometry (EDX). It is found that coarse B particles are heterogeneously precipitated at the E particle interface after water quenching and isothermal aging at 120 degrees C. The incoherent E/Al interface is responsible for the high tendency of heterogeneous precipitation of the B phase. Two different orientation relationships (ORs) between the eta, E and Al matrix are identified: OR1 [2 (11) over bar0](eta)[011](E)//[(1) over bar 12](Al), (01 (1) over bar0)(eta)//(13 (3) over bar)(E)//(201)(Al), OR2 [(1) over bar 12](E)//[0001](eta)//[011](Al), (01 (1) over bar0 )(eta)//(220)(E)//(34 (4) over bar)(Al). The eta phase is preferential to nucleate along the {111}(E) or the {220}(E) planes, depending on its OR. The heterogeneous nucleation of B phase on the E particle could stabilize the E/Al interface by introducing a coherent E/eta interface, which increases the drive force of heterogeneous precipitation. The reorientation of eta phase and mutual diffusion of solute atoms could assist the coherency of the E/eta interface. The present results suggest that increasing the coherency of the E/Al interface is a promising method to suppress the heterogeneous precipitation of the eta phase. (C) 2020 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000579868900103 Publication Date 2020-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0925-8388 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.133 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.133
Call Number UA @ admin @ c:irua:173503 Serial 6717
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Author (up) Ding, L.; Zhao, M.; Ehlers, F.J.H.; Jia, Z.; Zhang, Z.; Weng, Y.; Schryvers, D.; Liu, Q.; Idrissi, H.
Title “Branched” structural transformation of the L12-Al3Zr phase manipulated by Cu substitution/segregation in the Al-Cu-Zr alloy system Type A1 Journal Article
Year 2024 Publication Journal of materials science & technology Abbreviated Journal Journal of Materials Science & Technology
Volume 185 Issue Pages 186-206
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The effect of Cu on the evolution of the Al3Zr phase in an Al-Cu-Zr cast alloy during solution treatment at 500 °C has been thoroughly studied by combining atomic resolution high-angle annular dark-field scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy and first-principles cal- culations. The heat treatment initially produces a pure L12-Al3Zr microstructure, allowing for about 13 % Cu to be incorporated in the dispersoid. Cu incorporation increases the energy barrier for anti-phase boundary (APB) activation, thus stabilizing the L12 structure. Additional heating leads to a Cu-induced “branched”path for the L12 structural transformation, with the latter process accelerated once the first APB has been created. Cu atoms may either (i) be repelled by the APBs, promoting the transformation to a Cu-poor D023 phase, or (ii) they may segregate at one Al-Zr layer adjacent to the APB, promoting a transformation to a new thermodynamically favored phase, Al4CuZr, formed when these segregation layers are periodically arranged. Theoretical studies suggest that the branching of the L12 transformation path is linked to the speed at which an APB is created, with Cu attraction triggered by a comparatively slow process. This unexpected transformation behavior of the L12-Al3Zr phase opens a new path to understanding, and potentially regulating the Al3Zr dispersoid evolution for high temperature applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001154261100001 Publication Date 2023-12-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1005-0302 ISBN Additional Links UA library record; WoS full record
Impact Factor 10.9 Times cited Open Access Not_Open_Access
Notes This work was supported by the National Key Research and Development Program (No. 2020YFA0405900), the National Natural Science Foundation of China (Grant No. 52371111 and U2141215 ), the Natural Science Foundation of Jiangsu Province (No. BE2022159 ). We are grateful to the High Performance Computing Center of Nanjing Tech University for supporting the computational resources. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR- FNRS). Approved Most recent IF: 10.9; 2024 IF: 2.764
Call Number EMAT @ emat @c:irua:202392 Serial 8981
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Author (up) Dobysheva, L.V.; Potapov, P.L.; Schryvers, D.
Title Electron-energy-loss spectra of NiO Type A1 Journal article
Year 2004 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 69 Issue Pages 184404,1-6
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000222095500034 Publication Date 2004-05-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 17 Open Access
Notes Approved Most recent IF: 3.836; 2004 IF: 3.075
Call Number UA @ lucian @ c:irua:51059 Serial 930
Permanent link to this record