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Author Idrissi, H.; Turner, S.; Mitsuhara, M.; Wang, B.; Hata, S.; Coulombier, M.; Raskin, J.-P.; Pardoen, T.; Van Tendeloo, G.; Schryvers, D.
Title Point defect clusters and dislocations in FIB irradiated nanocrystalline aluminum films : an electron tomography and aberration-corrected high-resolution ADF-STEM study Type A1 Journal article
Year 2011 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal
Volume 17 Issue 6 Pages 983-990
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Focused ion beam (FIB) induced damage in nanocrystalline Al thin films has been characterized using advanced transmission electron microscopy techniques. Electron tomography was used to analyze the three-dimensional distribution of point defect clusters induced by FIB milling, as well as their interaction with preexisting dislocations generated by internal stresses in the Al films. The atomic structure of interstitial Frank loops induced by irradiation, as well as the core structure of Frank dislocations, has been resolved with aberration-corrected high-resolution annular dark-field scanning TEM. The combination of both techniques constitutes a powerful tool for the study of the intrinsic structural properties of point defect clusters as well as the interaction of these defects with preexisting or deformation dislocations in irradiated bulk or nanostructured materials.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge, Mass. Editor
Language Wos 000297832300018 Publication Date 2011-10-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1431-9276;1435-8115; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 1.891 Times cited 25 Open Access
Notes Iap; Fwo Approved Most recent IF: 1.891; 2011 IF: 3.007
Call Number UA @ lucian @ c:irua:93627 Serial 2653
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Author Heidari, H.; Rivero, G.; Idrissi, H.; Ramachandran, D.; Cakir, S.; Egoavil, R.; Kurttepeli, M.; Crabbé, A.C.; Hauffman, T.; Terryn, H.; Du Prez, F.; Schryvers, D.
Title Melamine–Formaldehyde Microcapsules: Micro- and Nanostructural Characterization with Electron Microscopy Type A1 Journal article
Year 2016 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal
Volume 22 Issue 22 Pages 1222-1232
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A systematic study has been carried out to compare the surface morphology, shell thickness, mechanical properties, and binding behavior of melamine–formaldehyde microcapsules of 5–30 μm diameter size with various amounts of core content by using scanning and transmission electron microscopy including electron tomography, in situ nanomechanical tensile testing, and electron energy-loss spectroscopy. It is found that porosities are present on the outside surface of the capsule shell, but not on the inner surface of the shell. Nanomechanical tensile tests on the capsule shells reveal that Young’s modulus of the shell material is higher than that of bulk melamine–formaldehyde and that the shells exhibit a larger fracture strain compared with the bulk. Core-loss elemental analysis of microcapsules embedded in epoxy indicates that during the curing process, the microcapsule-matrix interface remains uniform and the epoxy matrix penetrates into the surface micro-porosities of the capsule shells.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000393853100011 Publication Date 2016-12-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1431-9276 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 1.891 Times cited 2 Open Access
Notes This work was supported by SIM vzw, Technologiepark 935, BE-9052 Zwijnaarde, Belgium, within the InterPoCo project of the H-INT-S horizontal program. The authors are also thankful to Stijn Van den Broeck and Dr. Frederic Leroux for help in sample preparation and to S. Bals and J. Verbeeck for valuable discussions. H.I. acknowledges the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs, under Contract No. P7/21. Approved Most recent IF: 1.891
Call Number EMAT @ emat @ c:irua:138980 Serial 4333
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Author Amin-Ahmadi, B.; Idrissi, H.; Galceran, M.; Colla, M.S.; Raskin, J.P.; Pardoen, T.; Godet, S.; Schryvers, D.
Title Effect of deposition rate on the microstructure of electron beam evaporated nanocrystalline palladium thin films Type A1 Journal article
Year 2013 Publication Thin solid films : an international journal on the science and technology of thin and thick films Abbreviated Journal Thin Solid Films
Volume 539 Issue Pages 145-150
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The influence of the deposition rate on the formation of growth twins in nanocrystalline Pd films deposited by electron beam evaporation is investigated using transmission electron microscopy. Statistical measurements prove that twin boundary (TB) density and volume fraction of grains containing twins increase with increasing deposition rate. A clear increase of the dislocation density was observed for the highest deposition rate of 5 Å/s, caused by the increase of the internal stress building up during deposition. Based on crystallographic orientation indexation using transmission electron microscopy, it can be concluded that a {111} crystallographic texture increases with increasing deposition rate even though the {101} crystallographic texture remains dominant. Most of the TBs are fully coherent without any residual dislocations. However, for the highest deposition rate (5 Å/s), the coherency of the TBs decreases significantly as a result of the interaction of lattice dislocations emitted during deposition with the growth TBs. The analysis of the grain boundary character of different Pd films shows that an increasing fraction of high angle grain boundaries with misorientation angles around 5565° leads to a higher potential for twin formation.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000321111100025 Publication Date 2013-05-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0040-6090; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 1.879 Times cited 13 Open Access
Notes Fwo Approved Most recent IF: 1.879; 2013 IF: 1.867
Call Number UA @ lucian @ c:irua:109268 Serial 807
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Author Idrissi, H.; Amin-Ahmadi, B.; Wang, B.; Schryvers, D.
Title Review on TEM analysis of growth twins in nanocrystalline palladium thin films : toward better understanding of twin-related mechanisms in high stacking fault energy metals Type A1 Journal article
Year 2014 Publication Physica status solidi: B: basic research Abbreviated Journal Phys Status Solidi B
Volume 251 Issue 6 Pages 1111-1124
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Various modes of transmission electron microscopy including aberration corrected imaging were used in order to unravel the fundamental mechanisms controlling the formation of growth twins and the evolution of twin boundaries under mechanical and hydrogen loading modes in nanocrystalline (nc) palladium thin films. The latter were produced by electron-beam evaporation and sputter deposition and subjected to uniaxial tensile deformation as well as hydriding/dehydriding cycles. The results show that the twins form by dissociation of grain boundaries. The coherency of Σ3{111} coherent twin boundaries considerably decreases with deformation due to dislocation/twin boundary interactions while Σ3{112} incoherent twin boundaries dissociate under hydrogen cycling into two-phase boundaries bounding a new and unstable 9R phase. The effect of these elementary mechanisms on the macroscopic behavior of the palladium films is discussed and compared to recent experimental and simulation works in the literature. The results provide insightful information to guide the production of well-controlled population of growth twins in high stacking fault energy nc metallic thin films. The results also indicate directions for further enhancement of the mechanical properties of palladium films as needed for instance in palladium-based membranes in hydrogen applications.
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000337608600001 Publication Date 2014-02-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-1972; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 1.674 Times cited 7 Open Access
Notes Iap P7/21; Fwo G012012n Approved Most recent IF: 1.674; 2014 IF: 1.489
Call Number UA @ lucian @ c:irua:114580 Serial 2905
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Author Boulay, E.; Nakano, J.; Turner, S.; Idrissi, H.; Schryvers, D.; Godet, S.
Title Critical assessments and thermodynamic modeling of BaO-SiO2 and SiO2-TiO2 systems and their extensions into liquid immiscibility in the BaO-SiO2-TiO2 system Type A1 Journal article
Year 2014 Publication Calphad computer coupling of phase diagrams and thermochemistry Abbreviated Journal Calphad
Volume 47 Issue Pages 68-82
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract This study discusses rational reproduction of liquid immiscibility in the BaO-SiO2-TiO2 system. While a ternary assessment requires sub-binary descriptions in the same thermodynamic model, the related sub-binary systems BaO-SiO2, BaO-TiO2 and SiO2-TiO2 liquid and solid phases have been evaluated using different thermodynamic models in the literature. In this study, BaO-SiO2 and SiO2-TiO2 were assessed using the Ionic Two Sublattice model (I2SL) based on experimental data from the literature. BaO-TiO2 was already assessed using this model. Binary descriptions developed were then used for the assessment of liquid immiscibility in the BaO-SiO2-TiO2 system. Ternary interaction parameters were found necessary for rational reproduction of the new ternary experimental data gathered in the present work. The model parameters for each system were evaluated using a CAPLHAD approach. A set of parameters is proposed. They show good agreement between the calculated and experimental equilibrium liquidus, liquid immiscibility and thermochemical properties in the BaO-SiO2-TiO2 system. (C) 2014 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000346224700008 Publication Date 2014-07-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0364-5916; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 1.6 Times cited 9 Open Access
Notes Approved Most recent IF: 1.6; 2014 IF: 1.370
Call Number UA @ lucian @ c:irua:122776 Serial 540
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Author Idrissi, H.; Renard, K.; Schryvers, D.; Jacques, P.J.
Title TEM investigation of the formation mechanism of deformation twins in Fe-Mn-Si-Al TWIP steels Type A1 Journal article
Year 2013 Publication Philosophical magazine Abbreviated Journal Philos Mag
Volume 93 Issue 35 Pages 4378-4391
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The microstructure of a Fe-Mn-Si-Al twinning-induced plasticity (TWIP) steel exhibiting remarkable work hardening rate under uniaxial tensile deformation was investigated using transmission electron microscopy to uncover the mechanism(s) controlling the nucleation and growth of the mechanically induced twins. The results show that the stair-rod cross-slip deviation mechanism is necessary for the formation of the twins, while large extrinsic stacking faults homogenously distributed within the grains could act as preferential sources for the activation of the deviation process. The influence of such features on the thickness and strength of the twins and the resulting mechanical behaviour is discussed and compared to similar works recently performed on Fe-Mn-C TWIP steels.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000327478300005 Publication Date 2013-09-12
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 (down) 1.505 Times cited 15 Open Access
Notes Approved Most recent IF: 1.505; 2013 IF: 1.427
Call Number UA @ lucian @ c:irua:112815 Serial 3478
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Author Idrissi, H.; Cordier, P.; Jacob, D.; Walte, N.
Title Dislocations and plasticity of experimentally deformed coesite Type A1 Journal article
Year 2008 Publication European journal of mineralogy Abbreviated Journal Eur J Mineral
Volume 20 Issue 4 Pages 665-671
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Dislocation microstructures have been characterized by transmission electron microscopy in polycrystalline coesite deformed experimentally at 4 GPa, 1200 degrees C. Burgers vectors have been determined by large-angle convergent-beam electron diffraction. Sample orientation was assisted by precession electron diffraction to overcome difficulties arising from pseudo-hexagonal symmetry. The results are explained by using a pseudo-hexagonal setting. We found that most dislocations observed are of the 1/3 < 2 (1) over bar(1) over bar0 > type. No clear glide plane was identified, suggesting that climb is activated under these conditions. This conclusion is supported by the observation of numerous subgrain boundaries. We have also observed some [00011 dislocations. Finally, the C12/cl space group to which coesite belongs being centred, an additional slip system is observed: 1/6[(1) over bar2 (1) over bar3](01 (1) over bar1) (1/2[(1) over bar 10](110) in the monoclinic setting).
Address
Corporate Author Thesis
Publisher Place of Publication Stuttgart Editor
Language Wos 000262891900021 Publication Date 2008-08-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-1221; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 1.362 Times cited 5 Open Access
Notes Approved Most recent IF: 1.362; 2008 IF: 1.220
Call Number UA @ lucian @ c:irua:94604 Serial 733
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Author Renard, K.; Idrissi, H.; Schryvers, D.; Jacques, P.J.
Title Multiscale characterization of the work hardening mechanisms in Fe-Mn based TWIP steels Type A1 Journal article
Year 2012 Publication Steel research international Abbreviated Journal Steel Res Int
Volume 83 Issue 4 Pages 385-390
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract When strained in tension, high-manganese austenitic twinning induced plasticity (TWIP) steels achieve very high strength and elongation before necking. The main hypotheses available in the literature about the origin of their excellent work hardening include deformation twinning and dynamic strain ageing. In order to provide some answers, various experiments at different scales were conducted on FeMnC steels and the Fe28 wt%Mn3.5 wt%Al2.8 wt%Si alloy. At a macroscopic scale, tensile tests were performed on all the studied grades. It was shown that, though the FeMnAlSi based alloy retains very high elongation, the FeMnC steels properties are even more extraordinary. Tensile tests at different strain rates with the help of digital image correlation were also performed on the Fe20 wt%Mn1.2 wt%C steel to study the PLC effect occurring in this type of steel. It is suggested that supplementary hardening could come from reorientation of MnC pairs in the cores of the dislocations. At a microscopic scale, the Fe20 wt%Mn1.2 wt%C TWIP steel and the FeMnAlSi grade were thoroughly investigated by means of in situ TEM analysis. In the FeMnC steel, the formed twins could also lead to a composite effect, since they contain plenty of sessile dislocations. In the FeMnAlSi alloy, mechanical twins are thicker and contain fewer defects, leading to a lower work hardening than the other grade.
Address
Corporate Author Thesis
Publisher Verlag Stahleisen Place of Publication Düsseldorf Editor
Language Wos 000302471600016 Publication Date 2012-02-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1611-3683; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 1.235 Times cited 12 Open Access
Notes Approved Most recent IF: 1.235; 2012 IF: 0.493
Call Number UA @ lucian @ c:irua:97391 Serial 2239
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Author Schryvers, D.; Van Aert, S.; Delville, R.; Idrissi, H.; Turner, S.; Salje, E.K.H.
Title Dedicated TEM on domain boundaries from phase transformations and crystal growth Type A1 Journal article
Year 2013 Publication Phase transitions Abbreviated Journal Phase Transit
Volume 86 Issue 1 Pages 15-22
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Investigating domain boundaries and their effects on the behaviour of materials automatically implies the need for detailed knowledge on the structural aspects of the atomic configurations at these interfaces. Not only in view of nearest neighbour interactions but also at a larger scale, often surpassing the unit cell, the boundaries can contain structural elements that do not exist in the bulk. In the present contribution, a number of special boundaries resulting from phase transformations or crystal growth and those recently investigated by advanced transmission electron microscopy techniques in different systems will be reviewed. These include macrotwins between microtwinned martensite plates in NiAl, austenite-single variant martensite habit planes in low hysteresis NiTiPd, nanotwins in non-textured nanostructured Pd and ferroelastic domain boundaries in CaTiO3. In all discussed cases these boundaries play an essential role in the properties of the respective materials.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos 000312586700003 Publication Date 2012-12-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0141-1594;1029-0338; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 1.06 Times cited Open Access
Notes Fwo; Iap Approved Most recent IF: 1.06; 2013 IF: 1.044
Call Number UA @ lucian @ c:irua:101222 Serial 612
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Author Idrissi, H.; Schryvers, D.
Title Investigation of the elementary mechanisms controlling dislocation/twin boundary interactions in fcc metals and alloys : from conventional to advanced TEM characterization Type H2 Book chapter
Year 2012 Publication Abbreviated Journal
Volume Issue Pages 1213-1224
Keywords H2 Book chapter; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Formatex Research Center Place of Publication S.l. Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 978-84-939843-6-6 Additional Links UA library record
Impact Factor (down) Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:104694 Serial 1737
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Author Idrissi, H.; Schryvers, D.; Salje, E.K.H.; Zhang, H.; Carpenter, M.A.; Moya, X.
Title Pinning of the martensitic microstructures by dislocations in Cu74.08Al23.13Be2.79 Type P1 Proceeding
Year 2009 Publication Abbreviated Journal
Volume Issue Pages 02029,1-02029,5
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract A single crystal of Cu74.08Al23.13Be2.79 undergoes a martensitic phase transition at 246K and 232K under heating and cooling, respectively. Surprisingly, the martensite phase is elastically much harder than the austenite phase showing that interfaces between various crystallographic variants are strongly pinned and can not be moved by external stress while the phase boundary between the austenite and martensite regions in the sample remains mobile. This unusual behavior was revealed by Dynamical Mechanical Analysis and Resonant Ultrasound Spectroscopy. Transmission Electron Microscopy shows that the pinning is generated by dislocations, which are inherited from the austenite phase. Such dislocations can hinder the movement of stacking faults in the 18R martensite structure or twin boundaries between martensite variants.
Address
Corporate Author Thesis
Publisher Edp Place of Publication Coutaboeuf Editor
Language Wos 000274582300033 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 (down) Times cited 2 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:81952 Serial 2626
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Author Idrissi, H.; Bollinger, C.; Boioli, F.; Schryvers, D.; Cordier, P.
Title Low-temperature plasticity of olivine revisited with in situ TEM nanomechanical testing Type A1 Journal article
Year 2016 Publication Science Advances Abbreviated Journal
Volume 2 Issue 2 Pages e1501671-e1501671
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The rheology of the lithospheric mantle is fundamental to understanding how mantle convection couples with plate tectonics. However, olivine rheology at lithospheric conditions is still poorly understood because experiments are difficult in this temperature range where rocks and mineral become very brittle. We combine techniques of quantitative in situ tensile testing in a transmission electron microscope and numerical modeling of dislocation dynamics to constrain the low-temperature rheology of olivine. We find that the intrinsic ductility of olivine at low temperature is significantly lower than previously reported values, which were obtained under strain-hardened conditions. Using this method, we can anchor rheological laws determined at higher temperature and can provide a better constraint on intermediate temperatures relevant for the lithosphere. More generally, we demonstrate the possibility of characterizing the mechanical properties of specimens, which can be available in the form of submillimeter-sized particles only.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000379620200043 Publication Date 2016-03-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2375-2548 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) Times cited 32 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:134983 Serial 4202
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Author Lumbeeck, G.; Delvaux, A.; Idrissi, H.; Proost, J.; Schryvers, D.
Title Analysis of internal stress build-up during deposition of nanocrystalline Ni thin films using transmission electron microscopy Type A1 Journal article
Year 2020 Publication Thin solid films : an international journal on the science and technology of thin and thick films Abbreviated Journal Thin Solid Films
Volume 707 Issue Pages 138076
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Ni thin films sputter-deposited at room temperature with varying Ar pressures were investigated with automated crystal orientation mapping in a transmission electron microscope to uncover the mechanisms controlling the internal stress build-up recorded in-situ during deposition. Large grains were found to induce behaviour similar to a stress-free nucleation layer. The measurements of grain size in most of the Ni thin films are in agreement with the island coalescence model. Low internal stress was observed at low Ar pressure and was explained by the presence of large grains. Relaxation of high internal stress was also noticed at the highest Ar pressure, which was attributed to a decrease of Σ3 twin boundary density due to a low deposition rate. The results provide insightful information to better understand the relationship between structural boundaries and the evolution of internal stress upon deposition of thin films.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000539312200011 Publication Date 2020-05-12
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 (down) Times cited Open Access OpenAccess
Notes This work was supported by the Hercules Foundation [Grant No. AUHA13009], the Flemish Research Fund (FWO) [Grant No. G.0365.15N], and the Flemish Strategic Initiative for Materials (SIM) under the project InterPoCo. Thin film deposition has been realised as part of the WallonHY project, funded by the Public Service of Wallonia – Department of Energy and Sustainable Building. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). Approved Most recent IF: NA
Call Number EMAT @ emat @c:irua:169708 Serial 6370
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Author Bagherpour, A.; Baral, P.; Colla, M.-S.; Orekhov, A.; Idrissi, H.; Haye, E.; Pardoen, T.; Lucas, S.
Title Tailoring Mechanical Properties of a-C:H:Cr Coatings Type A1 Journal Article
Year 2023 Publication Coatings Abbreviated Journal Coatings
Volume 13 Issue 12 Pages 2084
Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
Abstract The development of coatings with tunable performances is critical to meet a wide range of technological applications each one with different requirements. Using the plasma-enhanced chemical vapor deposition (PECVD) process, scientists can create hydrogenated amorphous carbon coatings doped with metal (a-C:H:Me) with a broad range of mechanical properties, varying from those resembling polymers to ones resembling diamond. These diverse properties, without clear relations between the different families, make the material selection and optimization difficult but also very rich. An innovative approach is proposed here based on projected performance indices related to fracture energy, strength, and stiffness in order to classify and optimize a-C:H:Me coatings. Four different a-C:H:Cr coatings deposited by PECVD with Ar/C2H2 discharge under different bias voltage and pressures are investigated. A path is found to produce coatings with a selective critical energy release rate between 5–125 J/m2 without compromising yield strength (1.6–2.7 GPa) and elastic limit (≈0.05). Finally, fine-tuned coatings are categorized to meet desired applications under different testing conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001136013600001 Publication Date 2023-12-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2079-6412 ISBN Additional Links UA library record; WoS full record
Impact Factor (down) Times cited Open Access
Notes Walloon region under the PDR FNRS, C 62/5—PDR/OL 33677636 ; Belgian National Fund for Scientific Research, CDR—J.0113.20 ; National Fund for Scientific Reaserch; Approved Most recent IF: NA
Call Number EMAT @ emat @c:irua:202390 Serial 8982
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Author Sandfeld, S.; Samaee, V.; Idrissi, H.; Groten, J.; Pardoen, T.; Schwaiger, R.; Schryvers, D.
Title Datasets for the analysis of dislocations at grain boundaries and during vein formation in cyclically deformed Ni micropillars Type A1 Journal article
Year 2019 Publication Data in Brief Abbreviated Journal
Volume 27 Issue 27 Pages 104724
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The dataset together with the corresponding Python scripts and Jupyter notebooks presented in this article are supplementary data for the work presented in Samaee et al., 2019 [1]. The data itself consists of two parts: the simulation data that was used in [1] to analyze the effect of a particular grain boundary on curved dislocations and the precession electron diffraction (PED) strain maps together with post-processed data for analyzing details of the observed dislocation vein structures. Additionally, the complete stress tensor components, which are not shown in [1], have also been included. The data sets are accompanied by Python code explaining the file formats and showing how to post-process the data. (c) 2019 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000501988200181 Publication Date 2019-11-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2352-3409 ISBN Additional Links UA library record; WoS full record
Impact Factor (down) Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:165092 Serial 6292
Permanent link to this record
 

 
Author Marteleur, M.; Idrissi, H.; Amin-Ahmadi, B.; Prima, F.; Schryvers, D.; Jacques, P.J.
Title On the nucleation mechanism of {112} < 111 > mechanical twins in as-quenched beta metastable Ti-12 wt.% Mo alloy Type A1 Journal article
Year 2019 Publication Materialia Abbreviated Journal
Volume 7 Issue Pages Unsp 100418
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Recently developed beta-metastable Ti grades take advantage of the simultaneous activation of TRIP and TWIP effects for enhancing their work hardening rate. However, the role of each plasticity mechanism on the macroscopic mechanical response is still unclear. In this work, the nucleation mechanism of the first activated plasticity mechanism, namely {112} < 111 > twinning, was investigated. Firstly, post-mortem TEM analysis showed that twins nucleate on pre-existing microstructural defects such as thermal jogs with the zonal dislocation mechanism. The precipitation of the omega phase on twin boundaries has been observed, as well as the emission of numerous dislocations from super-jogs present in these twin boundaries. It is also shown that {112} < 111 > twins act as effective dislocation sources for the subsequent plasticity mechanisms such as beta -> alpha '' martensitic transformation and {332} < 111 > twinning. Secondly, in situ TEM tensile testing of the investigated Ti grade highlighted the primary role of the initial defect configuration present in the microstructure. It is shown that twins cannot nucleate without the presence of specific defects allowing the triggering of the dislocation decomposition needed for the twinning mechanism highlighted in investigated bulk samples.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000537131000052 Publication Date 2019-07-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2589-1529 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:170326 Serial 6875
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Author Samaeeaghmiyoni, V.; Cordier, P.; Demouchy, S.; Bollinger, C.; Gasc, J.; Mussi, A.; Schryvers, D.; Idrissi, H.
Title Research data supporting for Stress-induced amorphization triggers deformation in the lithospheric mantle Type Dataset
Year 2020 Publication Abbreviated Journal
Volume Issue Pages
Keywords Dataset; Electron microscopy for materials research (EMAT)
Abstract
Address
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 (down) Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:180668 Serial 6881
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Author Idrissi, H.; Samaee, V.; Lumbeeck, G.; van der Werf, T.; Pardoen, T.; Schryvers, D.; Cordier, P.
Title Supporting data for “In situ Quantitative Tensile Tests on Antigorite in a Transmission Electron Microscope” Type Dataset
Year 2019 Publication Abbreviated Journal
Volume Issue Pages
Keywords Dataset; Electron microscopy for materials research (EMAT)
Abstract The determination of the mechanical properties of serpentinites is essential towards the understanding of the mechanics of faulting and subduction. Here, we present the first in situ tensile tests on antigorite in a transmission electron microscope. A push-to-pull deformation device is used to perform quantitative tensile tests, during which force and displacement are measured, while the microstructure is imaged with the microscope. The experiments have been performed at room temperature on beams prepared by focused ion beam. The specimens are not single crystals despite their small sizes. Orientation mapping indicated that some grains were well-oriented for plastic slip. However, no dislocation activity has been observed even though engineering tensile stress went up to 700 MPa. We show also that antigorite does not exhibit an pure elastic-brittle behaviour since, despite the presence of defects, the specimens underwent plastic deformation and did not fail within the elastic regime. Instead, we observe that strain localizes at grain boundaries. All observations concur to show that under our experimental conditions, grain boundary sliding is the dominant deformation mechanism. This study sheds a new light on the mechanical properties of antigorite and calls for further studies on the structure and properties of grain boundaries in antigorite and more generally in phyllosilicates.
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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 (down) Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:169107 Serial 6891
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Author Lezaack, M.B.; Hannard, F.; Zhao, L.; Orekhov, A.; Adrien, J.; Miettinen, A.; Idrissi, H.; Simar, A.
Title Towards ductilization of high strength 7XXX aluminium alloys via microstructural modifications obtained by friction stir processing and heat treatments Type A1 Journal article
Year 2021 Publication Materialia Abbreviated Journal
Volume 20 Issue Pages 101248
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract High strength 7XXX aluminium series reach exceptional strength, higher than all other industrial aluminium alloys. However, they suffer from a lack of ductility compared to softer series. This work presents a procedure to improve the ductility of 7475 Al alloy in high strength condition, reaching a true fracture strain of 70% at full 500 MPa T6 yield strength. Using friction stir processing (FSP) and post-FSP heat treatments, 100% of industrial rolled material T6 yield stress is maintained but a 180% increase in fracture strain is measured for the processed material. This ductility improvement is studied by in-situ synchrotron X-ray tomography and is explained by the reduction of intermetallic particles size and the homogenization of their spatial distribution. Furthermore, the microstructure after FSP shows equiaxed refined grains which favour crack deviation as opposed to large cracks parallel to the elongated coarse grains in rolled plate. These results are paving the way to better formability and crashworthiness of 7XXX alloys.
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Publisher Place of Publication Editor
Language Wos 000718127100006 Publication Date 2021-10-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2589-1529 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:184145 Serial 6894
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Author Poulain, R.; Lumbeeck, G.; Hunka, J.; Proost, J.; Savolainen, H.; Idrissi, H.; Schryvers, D.; Gauquelin, N.; Klein, A.
Title Electronic and chemical properties of nickel oxide thin films and the intrinsic defects compensation mechanism Type A1 Journal article
Year 2022 Publication ACS applied electronic materials Abbreviated Journal
Volume 4 Issue 6 Pages 2718-2728
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Although largely studied, contradictory results on nickel oxide (NiO) properties can be found in the literature. We herein propose a comprehensive study that aims at leveling contradictions related to NiO materials with a focus on its conductivity, surface properties, and the intrinsic charge defects compensation mechanism with regards to the conditions preparation. The experiments were performed by in situ photo-electron spectroscopy, electron energy loss spectroscopy, and optical as well as electrical measurements on polycrystalline NiO thin films prepared under various preparation conditions by reactive sputtering. The results show that surface and bulk properties were strongly related to the deposition temperature with in particular the observation of Fermi level pinning, high work function, and unstable oxygen-rich grain boundaries for the thin films produced at room temperature but not at high temperature (>200 degrees C). Finally, this study provides substantial information about surface and bulk NiO properties enabling to unveil the origin of the high electrical conductivity of room temperature NiO thin films and also for supporting a general electronic charge compensation mechanism of intrinsic defects according to the deposition temperature.
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Publisher Place of Publication Editor
Language Wos 000819431200001 Publication Date 2022-06-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2637-6113 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:189555 Serial 7081
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Author Brognara, A.; Kashiwar, A.; Jung, C.; Zhang, X.; Ahmadian, A.; Gauquelin, N.; Verbeeck, J.; Djemia, P.; Faurie, D.; Dehm, G.; Idrissi, H.; Best, J.P.; Ghidelli, M.
Title Tailoring mechanical properties and shear band propagation in ZrCu metallic glass nanolaminates through chemical heterogeneities and interface density Type A1 Journal article
Year 2024 Publication Small Structures Abbreviated Journal
Volume Issue Pages 2400011-11
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The design of high‐performance structural thin films consistently seeks to achieve a delicate equilibrium by balancing outstanding mechanical properties like yield strength, ductility, and substrate adhesion, which are often mutually exclusive. Metallic glasses (MGs) with their amorphous structure have superior strength, but usually poor ductility with catastrophic failure induced by shear bands (SBs) formation. Herein, we introduce an innovative approach by synthesizing MGs characterized by large and tunable mechanical properties, pioneering a nanoengineering design based on the control of nanoscale chemical/structural heterogeneities. This is realized through a simplified model Zr 24 Cu 76 /Zr 61 Cu 39 , fully amorphous nanocomposite with controlled nanoscale periodicity ( Λ , from 400 down to 5 nm), local chemistry, and glass–glass interfaces, while focusing in‐depth on the SB nucleation/propagation processes. The nanolaminates enable a fine control of the mechanical properties, and an onset of crack formation/percolation (>1.9 and 3.3%, respectively) far above the monolithic counterparts. Moreover, we show that SB propagation induces large chemical intermixing, enabling a brittle‐to‐ductile transition when Λ  ≤ 50 nm, reaching remarkably large plastic deformation of 16% in compression and yield strength ≈2 GPa. Overall, the nanoengineered control of local heterogeneities leads to ultimate and tunable mechanical properties opening up a new approach for strong and ductile materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2024-05-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2688-4062 ISBN Additional Links UA library record
Impact Factor (down) Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:205798 Serial 9176
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