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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 1.505 Times cited 15 Open Access
Notes Approved Most recent IF: 1.505; 2013 IF: 1.427
Call Number (up) UA @ lucian @ c:irua:112815 Serial 3478
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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 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 (up) UA @ lucian @ c:irua:114580 Serial 2905
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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.
Address
Corporate Author Thesis
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 (up) UA @ lucian @ c:irua:114782 Serial 1614
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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.
Address
Corporate Author Thesis
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 (up) UA @ lucian @ c:irua:115555 Serial 3641
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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.
Address
Corporate Author Thesis
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 (up) UA @ lucian @ c:irua:116866 Serial 2649
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Author Proost, J.; Blaffart, F.; Turner, S.; Idrissi, H.
Title On the Origin of Damped Electrochemical Oscillations at Silicon Anodes (Revisited) Type A1 Journal article
Year 2014 Publication ChemPhysChem : a European journal of chemical physics and physical chemistry Abbreviated Journal Chemphyschem
Volume 15 Issue 14 Pages 3116-3124
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Electrochemical oscillations accompanying the formation of anodic silica have been shown in the past to be correlated with rather abrupt changes in the mechanical stress state of the silica film, commonly associated with some kind of fracture or porosification of the oxide. To advance the understanding on the origin of such oscillations in fluoride-free electrolytes, we have revisited a seminal experiment reported by Lehmann almost two decades ago. We thereby demonstrate that the oscillations are not stress-induced, and do not originate from a morphological transformation of the oxide in the course of anodisation. Alternatively, the mechanical features accompanying the oscillations can be explained by a partial relaxation of the field-induced electrostrictive stress. Furthermore, our observations suggest that the oscillation mechanism more likely results from a periodic depolarisation of the anodic silica.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000342770500029 Publication Date 2014-08-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1439-4235; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.075 Times cited 5 Open Access
Notes Approved Most recent IF: 3.075; 2014 IF: 3.419
Call Number (up) UA @ lucian @ c:irua:121086 Serial 2444
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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 1.6 Times cited 9 Open Access
Notes Approved Most recent IF: 1.6; 2014 IF: 1.370
Call Number (up) UA @ lucian @ c:irua:122776 Serial 540
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Author Lemoine, G.; Delannay, L.; Idrissi, H.; Colla, M.-S.; Pardoen, T.
Title Dislocation and back stress dominated viscoplasticity in freestanding sub-micron Pd films Type A1 Journal article
Year 2016 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 111 Issue 111 Pages 10-21
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A dislocation-based crystal plasticity model is developed in order to study the mechanical and creep/ relaxation behaviour of polycrystalline metallic thin films. The model accounts for the confinement of plasticity due to grain boundaries and for the anisotropy of individual grains, as well as for the significant viscoplastic effects associated to dislocation dominated thermally activated mechanisms. Numerical predictions are assessed based on experimental tensile test followed by relaxation on freestanding Pd films, based on an on-chip test technique. The dislocation-based mechanism assumption captures all the experimental trends, including the stress strain response, the relaxation behaviour and the dislocation density evolution, confirming the dominance of a dislocation driven deformation mechanism for the present Pd films with high defects density. The model has also been used to address some original experimental evidences involving back stresses, Bauschinger effect, backward creep and strain recovery. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000375812100002 Publication Date 2016-03-26
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 6 Open Access
Notes Approved Most recent IF: 5.301
Call Number (up) UA @ lucian @ c:irua:133636 Serial 4162
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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 Times cited 32 Open Access
Notes Approved Most recent IF: NA
Call Number (up) UA @ lucian @ c:irua:134983 Serial 4202
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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.
Address
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 (up) UA @ lucian @ c:irua:77276 Serial 1751
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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.
Address
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 (up) UA @ lucian @ c:irua:78542 Serial 1975
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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 Times cited 2 Open Access
Notes Approved Most recent IF: NA
Call Number (up) UA @ lucian @ c:irua:81952 Serial 2626
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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.
Address
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 (up) 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.
Address
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 (up) UA @ lucian @ c:irua:84472 Serial 2452
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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.
Address
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 (up) UA @ lucian @ c:irua:90103 Serial 3794
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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 1.891 Times cited 25 Open Access
Notes Iap; Fwo Approved Most recent IF: 1.891; 2011 IF: 3.007
Call Number (up) UA @ lucian @ c:irua:93627 Serial 2653
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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.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000301989500035 Publication Date 2012-02-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6454; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.301 Times cited 38 Open Access
Notes Iap Approved Most recent IF: 5.301; 2012 IF: 3.941
Call Number (up) UA @ lucian @ c:irua:94213 Serial 1465
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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 1.362 Times cited 5 Open Access
Notes Approved Most recent IF: 1.362; 2008 IF: 1.220
Call Number (up) UA @ lucian @ c:irua:94604 Serial 733
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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.
Address
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 (up) UA @ lucian @ c:irua:96955 Serial 3566
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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 1.235 Times cited 12 Open Access
Notes Approved Most recent IF: 1.235; 2012 IF: 0.493
Call Number (up) UA @ lucian @ c:irua:97391 Serial 2239
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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.
Address
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 (up) UA @ lucian @ c:irua:98374 Serial 2454
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