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Author | Idrissi, H.; Renard, K.; Ryelandt, L.; Schryvers, D.; Jacques, P.J. | ||||
Title | On the mechanism of twin formation in FeMnC TWIP steels | Type | A1 Journal article | ||
Year | 2010 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
Volume | 58 | Issue | 7 | Pages | 2464-2476 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Although it is well known that FeMnC TWIP steels exhibit high work-hardening rates, the elementary twinning mechanisms controlling the plastic deformation of these steels have still not been characterized. The aim of the present study is to analyse the extended defects related to the twinning occurrence using transmission electron microscopy. Based on these observations, the very early stage of twin nucleation can be attributed to the pole mechanism with deviation proposed by Cohen and Weertman or to the model of Miura, Takamura and Narita, while the twin growth is controlled by the pole mechanism proposed by Venables. High densities of sessile Frank dislocations are observed within the twins at the early stage of deformation, which can affect the growth and the stability of the twins, but also the strength of these twins and their interactions with the gliding dislocations present in the matrix. This experimental evidence is discussed and compared to recent results in order to relate the defects analysis to the macroscopic behaviour of this category of material. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000276523200018 | Publication Date | 2010-01-25 | |
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 | 244 | Open Access | |
Notes | Iap | Approved | Most recent IF: 5.301; 2010 IF: 3.791 | ||
Call Number | UA @ lucian @ c:irua:82270 | Serial | 2441 | ||
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Author | Idrissi, H.; Renard, K.; Schryvers, D.; Jacques, P.J. | ||||
Title | On the relationship between the twin internal structure and the work-hardening rate of TWIP steels | Type | A1 Journal article | ||
Year | 2010 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
Volume | 63 | Issue | 10 | Pages | 961-964 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | FeMnC and FeMnSiAl TWIP steels deformed under the same conditions exhibit different work-hardening rates. The present study investigates the microstructure of plastically deformed FeMnC and FeMnSiAl samples, particularly the internal structure of the mechanically generated twins and their topology at the grain scale. Twins in the FeMnC steel are finer and full of sessile dislocations, rendering this material distinctly stronger with an improved work-hardening rate. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000282461800003 | Publication Date | 2010-07-20 | |
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 | 145 | Open Access | |
Notes | Iap | Approved | Most recent IF: 3.747; 2010 IF: 2.820 | ||
Call Number | UA @ lucian @ c:irua:84472 | Serial | 2452 | ||
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Author | Idrissi, H.; Ryelandt, L.; Veron, M.; Schryvers, D.; Jacques, P.J. | ||||
Title | Is there a relationship between the stacking fault character and the activated mode of plasticity of FeMn-based austenitic steels? | Type | A1 Journal article | ||
Year | 2009 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
Volume | 60 | Issue | 11 | Pages | 941-944 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | By changing the testing temperature, an austenitic FeMnAlSi alloy presents either å-martensite transformation or mechanical twinning during straining. In order to understand the nucleation and growth mechanisms involved in both phenomena, defects and particularly stacking faults, were characterized by transmission electron microscopy. It is observed that the character of the stacking faults also changes (from extrinsic to intrinsic) together with the temperature and the activated mode of plasticity. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000265359900005 | Publication Date | 2009-02-10 | |
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 | 84 | Open Access | |
Notes | Iap | Approved | Most recent IF: 3.747; 2009 IF: 2.949 | ||
Call Number | UA @ lucian @ c:irua:77276 | Serial | 1751 | ||
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Author | Idrissi, H.; Wang, B.; Colla, M.S.; Raskin, J.P.; Schryvers, D.; Pardoen, T. | ||||
Title | Ultrahigh strain hardening in thin palladium films with nanoscale twins | Type | A1 Journal article | ||
Year | 2011 | Publication | Advanced materials | Abbreviated Journal | Adv Mater |
Volume | 23 | Issue | 18 | Pages | 2119-2122 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nanocrystalline Pd thin films containing coherent growth twin boundaries are deformed using on-chip nanomechanical testing. A large work-hardening capacity is measured. The origin of the observed behavior is unraveled using transmission electron microscopy and shows specific dislocations and twin boundaries interactions. The results indicate the potential for large strength and ductility balance enhancement in Pd films, as needed in membranes for H technologies. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Weinheim | Editor | ||
Language | Wos | 000291164200013 | Publication Date | 2011-04-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0935-9648; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 19.791 | Times cited | 57 | Open Access | |
Notes | Iap | Approved | Most recent IF: 19.791; 2011 IF: 13.877 | ||
Call Number | UA @ lucian @ c:irua:90103 | Serial | 3794 | ||
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Author | Wang, B.; Idrissi, H.; Galceran, M.; Colla, M.S.; Turner, S.; Hui, S.; Raskin, J.P.; Pardoen, T.; Godet, S.; Schryvers, D. | ||||
Title | Advanced TEM investigation of the plasticity mechanisms in nanocrystalline freestanding palladium films with nanoscale twins | Type | A1 Journal article | ||
Year | 2012 | Publication | International journal of plasticity | Abbreviated Journal | Int J Plasticity |
Volume | 37 | Issue | Pages | 140-156 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nanocrystalline palladium thin films deposited by electron-beam evaporation and deformed by on-chip tensile testing reveal a surprisingly large strain hardening capacity when considering the small similar to 25 nm grain size. The as-grown films contain several coherent single and multifold twin boundaries. The coherency of the twin boundaries considerably decreases with deformation due to dislocation/twin boundary interactions. These reactions are described based on a detailed analysis of the number and the type of dislocations located at the twin boundaries using high-resolution TEM, including aberration corrected microscopy. Sessile Frank dislocations were observed at the twin/matrix interfaces, explaining the loss of the TB coherency due to the Burgers vector pointing out of the twinning plane. Grain boundary mediated processes were excluded as a mechanism dominating the plastic deformation based on the investigation of the grain size distribution as well as the crystallographic texture using Automated Crystallographic Orientation Indexation TEM. Other factors influencing the plastic deformation such as impurities and the presence of a native passivation oxide layer at the surface of the films were investigated using analytical TEM. The twin boundaries observed in the present work partly explain the high strain hardening capacity by providing both increasing resistance to dislocation motion with deformation and a source for dislocation multiplication. (C) 2012 Elsevier Ltd. All rights reserved. | ||||
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Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000307416100009 | Publication Date | 2012-05-16 | |
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 | 44 | Open Access | |
Notes | Iap; Fwo | Approved | Most recent IF: 5.702; 2012 IF: 4.356 | ||
Call Number | UA @ lucian @ c:irua:101082 | Serial | 74 | ||
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Author | Ghidelli, M.; Idrissi, H.; Gravier, S.; Blandin, J.-J.; Raskin, J.-P.; Schryvers, D.; Pardoen, T. | ||||
Title | Homogeneous flow and size dependent mechanical behavior in highly ductile Zr 65 Ni 35 metallic glass films | Type | A1 Journal article | ||
Year | 2017 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
Volume | 131 | Issue | 131 | Pages | 246-259 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Motivated by recent studies demonstrating a high strength – high ductility potential of nano-scale metallic glass samples, the mechanical response of freestanding Zr65Ni35 film with sub-micron thickness has been investigated by combining advanced on-chip tensile testing and electron microscopy. Large deformation up to 15% is found for specimen thicknesses below 500 nm with variations depending on specimen size and frame compliance. The deformation is homogenous until fracture, with no evidence of shear banding. The yield stress is doubled when decreasing the specimen cross-section, reaching ~3 GPa for small cross-sections. The fracture strain variation is related to both the stability of the test device and to the specimen size. The study concludes on clear disconnect between the mechanisms controlling the onset of plasticity and the fracture process. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000402343400023 | Publication Date | 2017-03-31 | |
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 | 42 | Open Access | OpenAccess |
Notes | This work has been funded by the Belgian Science Policy through the IAP 7/21 project. We acknowledge IDS-FunMat for the PhD financial support.We thank the Renatech network and the PTA (Plateforme Technologique Amont) in Grenoble (France) for TFMG deposition facilities. The WINFAB infrastructure at the UCL and the help of R. Vayrette and M. Coulombier for the on-chip tests. H. Idrissi is currently mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). | Approved | Most recent IF: 5.301 | ||
Call Number | EMAT @ emat @ c:irua:142642 | Serial | 4562 | ||
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Author | Renard, K.; Idrissi, H.; Schryvers, D.; Jacques, P.J. | ||||
Title | On the stress state dependence of the twinning rate and work hardening in twinning-induced plasticity steels | Type | A1 Journal article | ||
Year | 2012 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
Volume | 66 | Issue | 12 | Pages | 966-971 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The influence of the stress state on the twinning rate and work hardening is studied in the case of an FeMnC TWIP steel strained in uniaxial tension, simple shear and rolling. The resulting stressstrain responses exhibit marked differences. The twinning rate, number of activated twinning systems in each grain, twin thickness and transmission of twins across grain boundaries are dependent on the imposed stress state during straining. Relationships between twin features and macroscopic work hardening rate are established. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000304641500004 | Publication Date | 2012-02-10 | |
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 | 41 | Open Access | |
Notes | Iap | Approved | Most recent IF: 3.747; 2012 IF: 2.821 | ||
Call Number | UA @ lucian @ c:irua:98374 | Serial | 2454 | ||
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Author | 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. | ||||
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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 | Salje, E.K.H.; Zhang, H.; Idrissi, H.; Schryvers, D.; Carpenter, M.A.; Moya, X.; Planes, A. | ||||
Title | Mechanical resonance of the austenite/martensite interface and the pinning of the martensitic microstructures by dislocations in Cu74.08Al23.13Be2.79 | Type | A1 Journal article | ||
Year | 2009 | Publication | Physical review: B: condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 80 | Issue | 13 | Pages | 134114,1-1134114,8 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A single crystal of Cu74.08Al23.13Be2.79 undergoes a martensitic phase transition at 246 and 232 K under heating and cooling, respectively. The phase fronts between the austenite and martensite regions of the sample are weakly mobile with a power-law resonance under external stress fields. Surprisingly, the martensite phase is elastically much harder than the austenite phase showing that interfaces between various crystallographic variants are strongly pinned and cannot be moved by external stress while the phase boundary between the austenite and martensite regions in the sample remains mobile. This unusual behavior was studied by dynamical mechanical analysis (DMA) and resonant ultrasound spectroscopy. The remnant strain, storage modulus, and internal friction were recorded simultaneously for different applied forces in DMA. With increasing forces, the remnant strain increases monotonously while the internal friction peak height shows a minimum at 300 mN. Transmission electron microscopy shows that the pinning is generated by dislocations which are inherited from the austenite phase. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Lancaster, Pa | Editor | ||
Language | Wos | 000271351300033 | Publication Date | 2009-10-22 | |
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 | 38 | Open Access | |
Notes | Multimat | Approved | Most recent IF: 3.836; 2009 IF: 3.475 | ||
Call Number | UA @ lucian @ c:irua:78542 | Serial | 1975 | ||
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Author | 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. | ||||
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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 | 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. | ||||
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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 | 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 | Ghidelli, M.; Orekhov, A.; Bassi, A.L.; Terraneo, G.; Djemia, P.; Abadias, G.; Nord, M.; Béché, A.; Gauquelin, N.; Verbeeck, J.; Raskin, J.-p.; Schryvers, D.; Pardoen, T.; Idrissi, H. | ||||
Title | Novel class of nanostructured metallic glass films with superior and tunable mechanical properties | Type | A1 Journal article | ||
Year | 2021 | Publication | Acta Materialia | Abbreviated Journal | Acta Mater |
Volume | Issue | Pages | 116955 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | A novel class of nanostructured Zr50Cu50 (%at.) metallic glass films with superior and tunable mechanical properties is produced by pulsed laser deposition. The process can be controlled to synthetize a wide range of film microstructures including dense fully amorphous, amorphous embedded with nanocrystals and amorphous nano-granular. A unique dense self-assembled nano-laminated atomic arrangement characterized by alternating Cu-rich and Zr/O-rich nanolayers with different local chemical enrichment and amorphous or amorphous-crystalline composite nanostructure has been discovered, while significant in-plane clustering is reported for films synthetized at high deposition pressures. This unique nanoarchitecture is at the basis of superior mechanical properties including large hardness and elastic modulus up to 10 and 140 GPa, respectively and outstanding total elongation to failure (>9%), leading to excellent strength/ductility balance, which can be tuned by playing with the film architecture. These results pave the way to the synthesis of novel class of engineered nanostructured metallic glass films with high structural performances attractive for a number of applications in microelectronics and coating industry. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000670077800004 | Publication Date | 2021-05-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1359-6454 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 5.301 | Times cited | 27 | Open Access | OpenAccess |
Notes | H.I. is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). This work was supported by the Fonds de la Recherche Scientifique – FNRS under Grant T.0178.19 and Grant CDR– J011320F. We acknowledge funding for the direct electron detector used in the 4D stem studies from the Hercules fund 'Direct electron detector for soft matter TEM' from the Flemish Government J.V acknowledges funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 823717 – ESTEEM3. A.O. has received partial funding from the GOA project “Solarpaint” of the University of Antwerp. A.B. and J.V. acknowledge funding through FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund. M.G. and A.L.B acknowledge Chantelle Ekanem for support in PLD depositions. | Approved | Most recent IF: 5.301 | ||
Call Number | EMAT @ emat @c:irua:178142 | Serial | 6761 | ||
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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. | ||||
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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 | 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 | Idrissi, H.; Kobler, A.; Amin-Ahmadi, B.; Coulombier, M.; Galceran, M.; Raskin, J.-P.; Godet, S.; Kuebel, C.; Pardoen, T.; Schryvers, D. | ||||
Title | Plasticity mechanisms in ultrafine grained freestanding aluminum thin films revealed by in-situ transmission electron microscopy nanomechanical testing | Type | A1 Journal article | ||
Year | 2014 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 104 | Issue | 10 | Pages | 101903 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In-situ bright field transmission electron microscopy (TEM) nanomechanical tensile testing and in-situ automated crystallographic orientation mapping in TEM were combined to unravel the elementary mechanisms controlling the plasticity of ultrafine grained Aluminum freestanding thin films. The characterizations demonstrate that deformation proceeds with a transition from grain rotation to intragranular dislocation glide and starvation plasticity mechanism at about 1% deformation. The grain rotation is not affected by the character of the grain boundaries. No grain growth or twinning is detected. (C) 2014 AIP Publishing LLC. | ||||
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Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000333082800022 | Publication Date | 2014-03-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951;1077-3118; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 24 | Open Access | |
Notes | Approved | Most recent IF: 3.411; 2014 IF: 3.302 | |||
Call Number | UA @ lucian @ c:irua:116866 | Serial | 2649 | ||
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Author | Wang, B.; Idrissi, H.; Shi, H.; Colla, M.S.; Michotte, S.; Raskin, J.P.; Pardoen, T.; Schryvers, D. | ||||
Title | Texture-dependent twin formation in nanocrystalline thin Pd films | Type | A1 Journal article | ||
Year | 2012 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
Volume | 66 | Issue | 11 | Pages | 866-871 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nanocrystalline Pd films were produced by electron-beam evaporation and sputter deposition. The electron-beam-evaporated films reveal randomly oriented nanograins with a relatively high density of growth twins, unexpected in view of the high stacking fault energy of Pd. In contrast, sputter-deposited films show a clear 〈1 1 1〉 crystallographic textured nanostructure without twins. These results provide insightful information to guide the generation of microstructures with enhanced strength/ductility balance in high stacking fault energy nanocrystalline metallic thin films. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000303621900007 | Publication Date | 2012-01-31 | |
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 | 19 | Open Access | |
Notes | Iap; Fwo | Approved | Most recent IF: 3.747; 2012 IF: 2.821 | ||
Call Number | UA @ lucian @ c:irua:96955 | Serial | 3566 | ||
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Author | Tang, X.; Reckinger, N.; Poncelet, O.; Louette, P.; Urena, F.; Idrissi, H.; Turner, S.; Cabosart, D.; Colomer, J.-F.; Raskin, J.-P.; Hackens, B.; Francis, L.A. | ||||
Title | Damage evaluation in graphene underlying atomic layer deposition dielectrics | Type | A1 Journal article | ||
Year | 2015 | Publication | Scientific reports | Abbreviated Journal | Sci Rep-Uk |
Volume | 5 | Issue | 5 | Pages | 13523 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Based on micro-Raman spectroscopy (muRS) and X-ray photoelectron spectroscopy (XPS), we study the structural damage incurred in monolayer (1L) and few-layer (FL) graphene subjected to atomic-layer deposition of HfO2 and Al2O3 upon different oxygen plasma power levels. We evaluate the damage level and the influence of the HfO2 thickness on graphene. The results indicate that in the case of Al2O3/graphene, whether 1L or FL graphene is strongly damaged under our process conditions. For the case of HfO2/graphene, muRS analysis clearly shows that FL graphene is less disordered than 1L graphene. In addition, the damage levels in FL graphene decrease with the number of layers. Moreover, the FL graphene damage is inversely proportional to the thickness of HfO2 film. Particularly, the bottom layer of twisted bilayer (t-2L) has the salient features of 1L graphene. Therefore, FL graphene allows for controlling/limiting the degree of defect during the PE-ALD HfO2 of dielectrics and could be a good starting material for building field effect transistors, sensors, touch screens and solar cells. Besides, the formation of Hf-C bonds may favor growing high-quality and uniform-coverage dielectric. HfO2 could be a suitable high-K gate dielectric with a scaling capability down to sub-5-nm for graphene-based transistors. | ||||
Address | ICTEAM Institute, Universite catholique de Louvain, Place du Levant 3, 1348 Louvain-la-Neuve, Belgium | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000360147400001 | Publication Date | 2015-08-27 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2045-2322; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.259 | Times cited | 18 | Open Access | |
Notes | The authors thank the staff of UCL’s Winfab and Welcome for technical support. Xiaohui Tang is a senior research of UCL. This work is financially supported by the Multi-Sensor-Platform for Smart Building Management project (No. 611887) and the Action de Recherche Concertée (ARC) “StressTronics”, Communauté française de Belgique. Part of this work is financially supported by the Belgian Fund for Scientific Research (FRS-FNRS) under FRFC contract “Chemographene” (No. 2.4577.11). J.-F. Colomer and B. Hackens are Research Associates of FRS-FNRS. This research used resources of the Electron Microscopy Service located at the University of Namur (“Plateforme Technologique Morphologie – Imagerie”). This research used resources of the ELISE Service of the University of Namur. This Service is member of the “Plateforme Technologique SIAM”. The research leading to this work has received partial funding from the European Union Seventh Framework Program under grant agreement No 604391 Graphene Flagship. | Approved | Most recent IF: 4.259; 2015 IF: 5.578 | ||
Call Number | c:irua:129193 | Serial | 3958 | ||
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Author | Leusink, D.P.; Coneri, F.; Hoek, M.; Turner, S.; Idrissi, H.; Van Tendeloo, G.; Hilgenkamp, H. | ||||
Title | Thin films of the spin ice compound Ho2Ti2O7 | Type | A1 Journal article | ||
Year | 2014 | Publication | APL materials | Abbreviated Journal | Apl Mater |
Volume | 2 | Issue | 3 | Pages | 032101-32107 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The pyrochlore compounds Ho2Ti2O7 and Dy2Ti2O7 show an exotic form of magnetism called the spin ice state, resulting from the interplay between geometrical frustration and ferromagnetic coupling. A fascinating feature of this state is the appearance of magnetic monopoles as emergent excitations above the degenerate ground state. Over the past years, strong effort has been devoted to the investigation of these monopoles and other properties of the spin ice state in bulk crystals. Here, we report the fabrication of Ho2Ti2O7 thin films using pulsed laser deposition on yttria-stabilized ZrO2 substrates. We investigated the structural properties of these films by X-ray diffraction, scanning transmission electron microscopy, and atomic force microscopy, and the magnetic properties by vibrating sample magnetometry at 2 K. The films not only show a high crystalline quality, but also exhibit the hallmarks of a spin ice: a pronounced magnetic anisotropy and an intermediate plateau in the magnetization along the [111] crystal direction. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000334220300002 | Publication Date | 2014-03-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2166-532X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.335 | Times cited | 18 | Open Access | |
Notes | The authors acknowledge support from the Dutch FOM and NWO foundations and from the European Union under the Framework 7 program under a contract from an Integrated Infrastructure Initiative (Reference 312483 ESTEEM2). G.V.T. acknowledges the ERC Grant N246791- COUNTATOMS. S.T. gratefully acknowledges financial support from the Fund for Scientific Research Flanders (FWO). H.I. acknowledges the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs under Contract No. P7/21. The microscope used in this study was partially financed by the Hercules Foundation of the Flemish Government. The authors acknowledge fruitful interactions with A. Brinkman, M. G. Blamire, M. Egilmez, F. J. G. Roesthuis, J. N. Beukers, C. G. Molenaar, M. Veldhorst, and X. Renshaw Wang; esteem2_ta | Approved | Most recent IF: 4.335; 2014 IF: NA | ||
Call Number | UA @ lucian @ c:irua:115555 | Serial | 3641 | ||
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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. | ||||
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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 | 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 | Turner, S.; Idrissi, H.; Sartori, A.F.; Korneychuck, S.; Lu, Y.-G.; Verbeeck, J.; Schreck, M.; Van Tendeloo, G. | ||||
Title | Direct imaging of boron segregation at dislocations in B:diamond heteroepitaxial films | Type | A1 Journal article | ||
Year | 2016 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 8 | Issue | 8 | Pages | 2212-2218 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | A thin film of heavily B-doped diamond has been grown epitaxially by microwave plasma chemical vapor deposition on an undoped diamond layer, on top of a Ir/YSZ/Si(001) substrate stack, to study the boron segregation and boron environment at the dislocations present in the film. The density and nature of the dislocations were investigated by conventional and weak-beam dark-field transmission electron microscopy techniques, revealing the presence of two types of dislocations: edge and mixed-type 45 degrees dislocations. The presence and distribution of B in the sample was studied using annular dark-field scanning transmission electron microscopy and spatially resolved electron energy-loss spectroscopy. Using these techniques, a segregation of B at the dislocations in the film is evidenced, which is shown to be intermittent along the dislocation. A single edge-type dislocation was selected to study the distribution of the boron surrounding the dislocation core. By imaging this defect at atomic resolution, the boron is revealed to segregate towards the tensile strain field surrounding the edge-type dislocations. An investigation of the fine structure of the B-K edge at the dislocation core shows that the boron is partially substitutionally incorporated into the diamond lattice and partially present in a lower coordination (sp(2)-like hybridization). | ||||
Address | EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. stuart.turner@uantwerpen.be | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000368860900053 | Publication Date | 2015-12-21 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.367 | Times cited | 15 | Open Access | |
Notes | S. T. acknowledges the fund for scien tific research Flanders (FWO) for a post-doctoral scholarship and under contract number G.0044.13N | Approved | Most recent IF: 7.367 | ||
Call Number | c:irua:131597UA @ admin @ c:irua:131597 | Serial | 4121 | ||
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Author | Guzzinati, G.; Altantzis, T.; Batuk, M.; De Backer, A.; Lumbeeck, G.; Samaee, V.; Batuk, D.; Idrissi, H.; Hadermann, J.; Van Aert, S.; Schryvers, D.; Verbeeck, J.; Bals, S. | ||||
Title | Recent Advances in Transmission Electron Microscopy for Materials Science at the EMAT Lab of the University of Antwerp | Type | A1 Journal article | ||
Year | 2018 | Publication | Materials | Abbreviated Journal | Materials |
Volume | 11 | Issue | 11 | Pages | 1304 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The rapid progress in materials science that enables the design of materials down to the nanoscale also demands characterization techniques able to analyze the materials down to the same scale, such as transmission electron microscopy. As Belgium’s foremost electron microscopy group, among the largest in the world, EMAT is continuously contributing to the development of TEM techniques, such as high-resolution imaging, diffraction, electron tomography, and spectroscopies, with an emphasis on quantification and reproducibility, as well as employing TEM methodology at the highest level to solve real-world materials science problems. The lab’s recent contributions are presented here together with specific case studies in order to highlight the usefulness of TEM to the advancement of materials science. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000444112800041 | Publication Date | 2018-07-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1996-1944 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.654 | Times cited | 15 | Open Access | OpenAccess |
Notes | Fonds Wetenschappelijk Onderzoek, G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N AUHA13009 ; European Research Council, COLOURATOM 335078 ; Universiteit Antwerpen, GOA Solarpaint ; G. Guzzinati, T. Altantzis and A. De Backer have been supported by postdoctoral fellowship grants from the Research Foundation Flanders (FWO). Funding was also received from the European Research Council (starting grant no. COLOURATOM 335078), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 770887), the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N, G.0401.16N) and from the University of Antwerp through GOA project Solarpaint. Funding for the TopSPIN precession system under grant AUHA13009, as well as for the Qu-Ant-EM microscope, is acknowledged from the HERCULES Foundation. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (F.R.S.-FNRS). (ROMEO:green; preprint:; postprint:can ; pdfversion:can); saraecas; ECAS_Sara; | Approved | Most recent IF: 2.654 | ||
Call Number | EMAT @ emat @c:irua:153737UA @ admin @ c:irua:153737 | Serial | 5064 | ||
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Author | Amin-Ahmadi, B.; Idrissi, H.; Delmelle, R.; Pardoen, T.; Proost, J.; Schryvers, D. | ||||
Title | High resolution transmission electron microscopy characterization of fcc -> 9R transformation in nanocrystalline palladium films due to hydriding | Type | A1 Journal article | ||
Year | 2013 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 102 | Issue | 7 | Pages | 071911-71914 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Sputtered nanocrystalline palladium thin films with nanoscale growth twins have been subjected to hydriding cycles. The evolution of the twin boundaries has been investigated using high resolution transmission electron microscopy. Surprisingly, the Sigma 3{112} incoherent twin boundaries dissociate after hydriding into two phase boundaries bounding a 9R phase. This phase which corresponds to single stacking faults located every three {111} planes in the fcc Pd structure was not expected because of the high stacking fault energy of Pd. This observation is connected to the influence of the Hydrogen on the stacking fault energy of palladium and the high compressive stresses building up during hydriding. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4793512] | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000315596700023 | Publication Date | 2013-02-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 14 | Open Access | |
Notes | Iap | Approved | Most recent IF: 3.411; 2013 IF: 3.515 | ||
Call Number | UA @ lucian @ c:irua:108303 | Serial | 1462 | ||
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Author | Amin-Ahmadi, B.; Connétable, D.; Fivel, M.; Tanguy, D.; Delmelle, R.; Turner, S.; Malet, L.; Godet, S.; Pardoen, T.; Proost, J.; Schryvers, D.; Idrissi, H. | ||||
Title | Dislocation/hydrogen interaction mechanisms in hydrided nanocrystalline palladium films | Type | A1 Journal article | ||
Year | 2016 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
Volume | 111 | Issue | 111 | Pages | 253-261 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The nanoscale plasticity mechanisms activated during hydriding cycles in sputtered nanocrystalline Pd films have been investigated ex-situ using advanced transmission electron microscopy techniques. The internal stress developing within the films during hydriding has been monitored in-situ. Results showed that in Pd films hydrided to β-phase, local plasticity was mainly controlled by dislocation activity in spite of the small grain size. Changes of the grain size distribution and the crystallographic texture have not been observed. In contrast, significant microstructural changes were not observed in Pd films hydrided to α-phase. Moreover, the effect of hydrogen loading on the nature and density of dislocations has been investigated using aberration-corrected TEM. Surprisingly, a high density of shear type stacking faults has been observed after dehydriding, indicating a significant effect of hydrogen on the nucleation energy barriers of Shockley partial dislocations. Ab-initio calculations of the effect of hydrogen on the intrinsic stable and unstable stacking fault energies of palladium confirm the experimental observations. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000375812100027 | Publication Date | 2016-04-06 | |
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 | 14 | Open Access | |
Notes | This work was carried out in the framework of the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs, under Contract No. P7/21. The support of the FWO research project G012012N “Understanding nanocrystalline mechanical behaviour from structural investigations” for B. Amin-Ahmadi is also gratefully acknowledged. This work was granted access to the HPC resources of CALMIP (CICT Toulouse, France) under the allocations 2014-p0912 and 2014-p0749. | Approved | Most recent IF: 5.301 | ||
Call Number | c:irua:132678 | Serial | 4054 | ||
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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. | ||||
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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 | 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 | 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. | ||||
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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 | 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. | ||||
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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 | 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 | van Oeffelen, L.; Van Roy, W.; Idrissi, H.; Charlier, D.; Lagae, L.; Borghs, G. | ||||
Title | Ion current rectification, limiting and overlimiting conductances in nanopores | Type | A1 Journal article | ||
Year | 2015 | Publication | PLoS ONE | Abbreviated Journal | Plos One |
Volume | 10 | Issue | 10 | Pages | e0124171 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Previous reports on Poisson-Nernst-Planck (PNP) simulations of solid-state nanopores have focused on steady state behaviour under simplified boundary conditions. These are Neumann boundary conditions for the voltage at the pore walls, and in some cases also Donnan equilibrium boundary conditions for concentrations and voltages at both entrances of the nanopore. In this paper, we report time-dependent and steady state PNP simulations under less restrictive boundary conditions, including Neumann boundary conditions applied throughout the membrane relatively far away from the nanopore. We simulated ion currents through cylindrical and conical nanopores with several surface charge configurations, studying the spatial and temporal dependence of the currents contributed by each ion species. This revealed that, due to slow co-diffusion of oppositely charged ions, steady state is generally not reached in simulations or in practice. Furthermore, it is shown that ion concentration polarization is responsible for the observed limiting conductances and ion current rectification in nanopores with asymmetric surface charges or shapes. Hence, after more than a decade of collective research attempting to understand the nature of ion current rectification in solid-state nanopores, a relatively intuitive model is retrieved. Moreover, we measured and simulated current-voltage characteristics of rectifying silicon nitride nanopores presenting overlimiting conductances. The similarity between measurement and simulation shows that overlimiting conductances can result from the increased conductance of the electric double-layer at the membrane surface at the depletion side due to voltage-induced polarization charges. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000354916100012 | Publication Date | 2015-05-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-6203; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.806 | Times cited | 11 | Open Access | |
Notes | Approved | Most recent IF: 2.806; 2015 IF: 3.234 | |||
Call Number | c:irua:126366 | Serial | 1744 | ||
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Author | Samaeeaghmiyoni, V.; Idrissi, H.; Groten, J.; Schwaiger, R.; Schryvers, D. | ||||
Title | Quantitative in-situ TEM nanotensile testing of single crystal Ni facilitated by a new sample preparation approach | Type | A1 Journal article | ||
Year | 2017 | Publication | Micron | Abbreviated Journal | Micron |
Volume | 94 | Issue | 94 | Pages | 66-73 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Twin-jet electro-polishing and Focused Ion Beam (FIB) were combined to produce small size Nickel single crystal specimens for quantitative in-situ nanotensile experiments in the transmission electron microscope. The combination of these techniques allows producing samples with nearly defect-free zones in the centre in contrast to conventional FIB-prepared samples. Since TEM investigations can be performed on the electro-polished samples prior to in-situ TEM straining, specimens with desired crystallographic orientation and initial microstructure can be prepared. The present results reveal a dislocation nucleation controlled plasticity, in which small loops induced by FIB near the edges of the samples play a central role. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000393247300008 | Publication Date | 2016-12-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0968-4328 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.98 | Times cited | 11 | Open Access | OpenAccess |
Notes | This research has been performed with the financial support of the Belgian Science Policy (Belspo) under the framework of the interuniversity attraction poles program, IAP7/21. Financial support from the Flemish (FWO) and German Research Foundation (DFG) through the European M-ERA.NET project “FaSS” (Fatigue Simulation near Surfaces) under the grant numbers GA.014.13N and SCHW855/5-1, respectively, is gratefully acknowledged. V. Samaeeaghmiyoni also acknowledges the FWO research project G012012N “Understanding nanocrystalline mechanical behaviour from structural investigations”. H. Idrissi is currently mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). | Approved | Most recent IF: 1.98 | ||
Call Number | EMAT @ emat @ c:irua:139515 | Serial | 4341 | ||
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Author | Boulay, E.; Ragoen, C.; Idrissi, H.; Schryvers, D.; Godet, S. | ||||
Title | Influence of amorphous phase separation on the crystallization behavior of glass-ceramics in the BaO-TiO2-SiO2 system | Type | A1 Journal article | ||
Year | 2014 | Publication | Journal of non-crystalline solids | Abbreviated Journal | J Non-Cryst Solids |
Volume | 384 | Issue | Pages | 61-72 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The possible role of a prior amorphous phase separation on the subsequent crystallization has been the topic of vigorous debates over the last decades and has not yet been clarified, especially regarding the role of the interfaces created by the phase separation. This study proposes to focus on the interplay between a prior amorphous phase separation and the crystallization of fresnoite in the BaO-TiO2-SiO2 system. The crystallization behavior of a non-stoichiometric composition inside the miscibility gap (called APS) is compared with the stoichiometric composition (called FRES) and a non-stoichiometric composition outside the miscibility gap (called NoAPS). The crystallization mechanisms are compared using differential thermal analysis (DTA) by calculating the Avrami parameters and the activation energies as a function of the particle size. The DTA study shows that the two non-stoichiometric compositions exhibit a pronounced surface crystallization behavior whereas FRES undergoes bulk nucleation. This is supported by a multi-scale microstructure characterization. Furthermore, this study demonstrates that the amorphous phase separation and the associated interfaces do not play any significant role in the nucleation step. Moreover, transmission electron microscope (TEM) and local orientation measurements show that the growth of the dendrites is not hindered by the SiO2-rich droplets. The final stage of crystallization of APS is tentatively explained by two composition effects that must be further investigated: the viscosity effect and the formation of a eutectic. (C) 2013 Elsevier B.V. All rights reserved. | ||||
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Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000329422400010 | Publication Date | 2013-07-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-3093; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.124 | Times cited | 10 | Open Access | |
Notes | Approved | Most recent IF: 2.124; 2014 IF: 1.766 | |||
Call Number | UA @ lucian @ c:irua:114782 | Serial | 1614 | ||
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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. | ||||
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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 | 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 | Li, K.; Idrissi, H.; Sha, G.; Song, M.; Lu, J.; Shi, H.; Wang, W.; Ringer, S.P.; Du, Y.; Schryvers, D. | ||||
Title | Quantitative measurement for the microstructural parameters of nano-precipitates in Al-Mg-Si-Cu alloys | Type | A1 Journal article | ||
Year | 2016 | Publication | Materials characterization | Abbreviated Journal | Mater Charact |
Volume | 118 | Issue | 118 | Pages | 352-362 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Size, number density and volume fraction of nano-precipitates are important microstructural parameters controlling the strengthening of materials. In this work a widely accessible, convenient, moderately time efficient method with acceptable accuracy and precision has been provided for measurement of volume fraction of nano-precipitates in crystalline materials. The method is based on the traditional but highly accurate technique of measuring foil thickness via convergent beam electron diffraction. A new equation is proposed and verified with the aid of 3-dimensional atom probe (3DAP) analysis, to compensate for the additional error resulted from the hardly distinguishable contrast of too short incomplete precipitates cut by the foil surface. The method can be performed on a regular foil specimen with a modem LaB6 or field-emission-gun transmission electron microscope. Precisions around +/- 16% have been obtained for precipitate volume fractions of needle-like beta ''/C and Q precipitates in an aged Al-Mg-Si-Cu alloy. The measured number density is dose to that directly obtained using 3DAP analysis by a misfit of 45%, and the estimated precision for number density measurement is about +/- 11%. The limitations of the method are also discussed. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000383292000042 | Publication Date | 2016-06-07 | |
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 | 9 | Open Access | |
Notes | This work is financially supported by National Natural Science Foundation of China (51501230 and 51531009) and Postdoctoral Science Foundation of Central South University (502042057). H.I. acknowledges the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs under Contract No. P7/21 and FWO project G.0576.09N. | Approved | Most recent IF: 2.714 | ||
Call Number | EMAT @ emat @ c:irua:137171 | Serial | 4334 | ||
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