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	Author	Ding, L.; Orekhov, A.; Weng, Y.; Jia, Z.; Idrissi, H.; Schryvers, D.; Muraishi, S.; Hao, L.; Liu, Q.
	Title	Study of the Q′ (Q)-phase precipitation in Al–Mg–Si–Cu alloys by quantification of atomic-resolution transmission electron microscopy images and atom probe tomography			Type	A1 Journal article
	Year	2019	Publication	Journal of materials science	Abbreviated Journal	J Mater Sci
	Volume	54	Issue	10	Pages	7943-7952
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The precipitation mechanism of the Q phase in Al-Mg-Si-Cu alloys has long been the subject of ambiguity and debate since its metastable phase (Q 0) has the same crystal structure and similar lattice parameters as its equilibrium counterparts. In the present work, the evolution of the Q 0 (Q) phase during aging is studied by combination of quantitative atomic-resolution scanning transmission electron microscopy and atom probe tomography. It was found that the transformation from the Q 0 to the Q phase involves changes of the occupancy of Al atoms in atomic columns of the Q 0 (Q) phase. The Al atoms incorporated in the Cu, Si and Mg columns are gradually released into the Al matrix, while mixing between Cu and Si atoms occurs in the Si columns. This transformation process is mainly attributed to the low lattice misfit of the equilibrium Q phase. Besides, the formation of various compositions of the Q phase is due to the different occupancy in the atomic columns of the Q phase. The occupancy changes in the columns of the Q phase are kinetically controlled and are strongly influenced by the alloy composition and aging temperature.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000460069500043	Publication Date	2019-02-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-2461	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.599	Times cited	1	Open Access	Not_Open_Access
	Notes	Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing, cstc2017zdcy-zdzxX0006 ; Fundamental Research Funds for the Central Universities of China, 2018CDGFCL0002 106112017CDJQJ308822 ; Belgian National Fund for Scientific Research; the National Natural Science Foundation of China, 51871035 ; This work was supported by the Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing (Grant No. cstc2017zdcyzdzxX0006), the Fundamental Research Funds for the Central Universities of China (Grant No. 2018CDGFCL0002), the National Natural Science Foundation of China (Grant No. 51871035) and the Foundation for Innovative Research Groups J Mater Sci National Natural Science Foundation of China (Grant No. 51421001). H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS).			Approved	Most recent IF: 2.599
	Call Number	EMAT @ emat @UA @ admin @ c:irua:158112			Serial	5158
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	Author	Samaee, V.; Sandfeld, S.; Idrissi, H.; Groten, J.; Pardoen, T.; Schwaiger, R.; Schryvers, D.
	Title	Dislocation structures and the role of grain boundaries in cyclically deformed Ni micropillars			Type	A1 Journal article
	Year	2020	Publication	Materials Science And Engineering A-Structural Materials Properties Microstructure And Processing	Abbreviated Journal	Mat Sci Eng A-Struct
	Volume	769	Issue		Pages	138295
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Transmission electron microscopy and finite element-based dislocation simulations were combined to study the development of dislocation microstructures after cyclic deformation of single crystal and bicrystal Ni micropillars oriented for multi-slip. A direct correlation between large accumulation of plastic strain and the presence of dislocation cell walls in the single crystal micropillars was observed, while the presence of the grain boundary hampered the formation of wall-like structures in agreement with a smaller accumulated plastic strain. Automated crystallographic orientation and nanostrain mapping using transmission electron microscopy revealed the presence of lattice heterogeneities associated to the cell walls including long range elastic strain fields. By combining the nanostrain mapping with an inverse modelling approach, information about dislocation density, line orientation and Burgers vector direction was derived, which is not accessible otherwise in such dense dislocation structures. Simulations showed that the image forces associated with the grain boundary in this specific bicrystal configuration have only a minor influence on dislocation behavior. Thus, the reduced occurrence of “mature” cell walls in the bicrystal can be attributed to the available volume, which is too small to accommodate cell structures.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000500373800018	Publication Date	2019-08-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0921-5093	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.4	Times cited	1	Open Access	OpenAccess
	Notes	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.014.13 N,SCHW855/5-1, and SA2292/2-1 is gratefully acknowledged. V.S. acknowledges the FWO research project G012012 N “Understanding nanocrystalline mechanical behaviour from structural investigations”. H.I. is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). S.S. acknowledges financial support from the European Research Council through the ERC Grant Agreement No. 759419 (MuDiLingo – A Multiscale Dislocation Language for Data- Driven Materials Science).			Approved	Most recent IF: 6.4; 2020 IF: 3.094
	Call Number	EMAT @ emat @c:irua:163475			Serial	5371
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	Author	Zhao, L.; Macias, J.G.S.; Ding, L.; Idrissi, H.; Simar, A.
	Title	Damage mechanisms in selective laser melted AlSi10Mg under as built and different post-treatment conditions			Type	A1 Journal article
	Year	2019	Publication	Microstructure And Processing	Abbreviated Journal	Mat Sci Eng A-Struct
	Volume	764	Issue	764	Pages	138210
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Selective laser melting (SLM) manufactured AlSi10Mg alloys present a fine silicon-rich network and precipitates which grant high mechanical strength but low ductility. Post-treatments, aiming at eliminating inherent defects related to SLM such as residual stresses, porosity or inhomogeneity, result in significant changes in the microstructure and impact both the hardening and the damage mechanisms of the post-treated material. The present work is dedicated to the investigation of the fracture of SLM AlSi10Mg under as built and three post-treatment conditions, namely two stress relieve heat treatments and friction stir processing (FSP). It is found that the interconnected Si network fosters damage at low strain due to the brittleness of the Si phase. The onset of damage transfers load to the enclosed Al phase which then fractures quickly under high stress, thus leading to low material ductility. In contrast, when the Si network is globularized into Si particles, the ductility is highly increased even in the case where the porosity and inhomogeneity of the microstructure remain after the post-treatment. The ductility enhancement results from the delay in void nucleation on the Si particles as well as from the tolerance for void growth in the Al matrix.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000486360100029	Publication Date	2019-07-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0921-5093	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.094	Times cited	1	Open Access
	Notes	; This research work has been supported by the WALInnov LongLifeAM project, Convention n 1810016, funded by Service public de Wallonie Economic Emploi Recherche (SPW-EER). L. Ding and A. Simar acknowledge the financial support of the European Research Council (ERC) for the Starting Grant ALUFIX project (grant agreement n 716678). J. G. Santos Macias acknowledges the support of the Fonds de la recherche scientifique -FNRS (FRIA grant), Belgium. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSRFNRS). Any-Shape is acknowledged for material supply. We thank Prof. P. J. Jacques from UCLouvain for fruitful discussion and critical reading of the paper. ;			Approved	Most recent IF: 3.094
	Call Number	UA @ admin @ c:irua:162800			Serial	5386
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	Author	Choisez, L.; Ding, L.; Marteleur, M.; Idrissi, H.; Pardoen, T.; Jacques, P.J.
	Title	High temperature rise dominated cracking mechanisms in ultra-ductile and tough titanium alloy			Type	A1 Journal article
	Year	2020	Publication	Nature Communications	Abbreviated Journal	Nat Commun
	Volume	11	Issue	1	Pages	2110
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Extensive use of titanium alloys is partly hindered by a lack of ductility, strain hardening, and fracture toughness. Recently, several beta -metastable titanium alloys were designed to simultaneously activate both transformation-induced plasticity and twinning-induced plasticity effects, resulting in significant improvements to their strain hardening capacity and resistance to plastic localization. Here, we report an ultra-large fracture resistance in a Ti-12Mo alloy (wt.%), that results from a high resistance to damage nucleation, with an unexpected fracture phenomenology under quasi-static loading. Necking develops at a large uniform true strain of 0.3 while fracture initiates at a true fracture strain of 1.0 by intense through-thickness shear within a thin localized shear band. Transmission electron microscopy reveals that dynamic recrystallization occurs in this band, while local partial melting is observed on the fracture surface. Shear band temperatures of 1250-2450 degrees C are estimated by the fusible coating method. The reported high ductility combined to the unconventional fracture process opens alternative avenues toward Ti alloys toughening. Specific titanium alloys combine transformation-induced plasticity and twinning-induced plasticity for improved work hardening. Here, the authors show that these alloys also have an ultra-large fracture resistance and an unexpected fracture mechanism via dynamic recrystallization and local melting in a deformation band.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000558816700010	Publication Date	2020-04-30
	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	16.6	Times cited	1	Open Access	OpenAccess
	Notes	; The Fonds National de Recherche Scientifique FNRS is gratefully acknowledged for the grant no. T.0127.19, the research grant of L.C. and the research mandate of H.I. The authors are thankful to J. Adrien and E. Maire for their help with the X-ray tomography analysis, to J.D. Embury for the fruitful discussions and to F. Prima for provisioning the material. ;			Approved	Most recent IF: 16.6; 2020 IF: 12.124
	Call Number	UA @ admin @ c:irua:171318			Serial	6536
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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 Cu_74.08Al_23.13Be_2.79			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	UA @ lucian @ c:irua:81952			Serial	2626
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	Author	Heidari, H.; Rivero, G.; Idrissi, H.; Ramachandran, D.; Cakir, S.; Egoavil, R.; Kurttepeli, M.; Crabbé, A.C.; Hauffman, T.; Terryn, H.; Du Prez, F.; Schryvers, D.
	Title	Melamine–Formaldehyde Microcapsules: Micro- and Nanostructural Characterization with Electron Microscopy			Type	A1 Journal article
	Year	2016	Publication	Microscopy and microanalysis	Abbreviated Journal	Microsc Microanal
	Volume	22	Issue	22	Pages	1222-1232
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A systematic study has been carried out to compare the surface morphology, shell thickness, mechanical properties, and binding behavior of melamine–formaldehyde microcapsules of 5–30 μm diameter size with various amounts of core content by using scanning and transmission electron microscopy including electron tomography, in situ nanomechanical tensile testing, and electron energy-loss spectroscopy. It is found that porosities are present on the outside surface of the capsule shell, but not on the inner surface of the shell. Nanomechanical tensile tests on the capsule shells reveal that Young’s modulus of the shell material is higher than that of bulk melamine–formaldehyde and that the shells exhibit a larger fracture strain compared with the bulk. Core-loss elemental analysis of microcapsules embedded in epoxy indicates that during the curing process, the microcapsule-matrix interface remains uniform and the epoxy matrix penetrates into the surface micro-porosities of the capsule shells.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000393853100011	Publication Date	2016-12-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1431-9276	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.891	Times cited	2	Open Access
	Notes	This work was supported by SIM vzw, Technologiepark 935, BE-9052 Zwijnaarde, Belgium, within the InterPoCo project of the H-INT-S horizontal program. The authors are also thankful to Stijn Van den Broeck and Dr. Frederic Leroux for help in sample preparation and to S. Bals and J. Verbeeck for valuable discussions. H.I. acknowledges the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs, under Contract No. P7/21.			Approved	Most recent IF: 1.891
	Call Number	EMAT @ emat @ c:irua:138980			Serial	4333
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	Author	Lumbeeck, G.; Idrissi, H.; Amin-Ahmadi, B.; Favache, A.; Delmelle, R.; Samaee, V.; Proost, J.; Pardoen, T.; Schryvers, D.
	Title	Effect of hydriding induced defects on the small-scale plasticity mechanisms in nanocrystalline palladium thin films			Type	A1 Journal Article
	Year	2018	Publication	Journal Of Applied Physics	Abbreviated Journal	J Appl Phys
	Volume	124	Issue	22	Pages	225105
	Keywords	A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
	Abstract	Nanoindentation tests performed on nanocrystalline palladium films subjected to hydriding/dehydriding cycles demonstrate a significant softening when compared to the as-received material. The origin of this softening is unraveled by combining in situ TEM nanomechanical testing with automated crystal orientation mapping in TEM and high resolution TEM. The softening is attributed to the presence of a high density of stacking faults and of Shockley partial dislocations after hydrogen loading. The hydrogen induced defects affect the elementary plasticity mechanisms and the mechanical response by acting as preferential sites for twinning/detwinning during deformation. These results are analyzed and compared to previous experimental and simulation works in the literature. This study provides new insights into the effect of hydrogen on the atomistic deformation and cracking mechanisms as well as on the mechanical properties of nanocrystalline thin films and membranes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000453254000025	Publication Date	2018-12-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	2	Open Access	Not_Open_Access
	Notes	This work was supported by the Hercules Foundation under Grant No. AUHA13009, the Flemish Research Fund (FWO) under Grant No. G.0365.15N, and the Flemish Strategic Initiative for Materials (SIM) under the project InterPoCo. Dr. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). We would like to thank Dr. Hadi Pirgazi from UGent for his technical support to process the ACOM data in the OIM Analysis software.			Approved	Most recent IF: 2.068
	Call Number	EMAT @ emat @c:irua:155742			Serial	5135
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	Author	Delvaux, A.; Lumbeeck, G.; Idrissi, H.; Proost, J.
	Title	Effect of microstructure and internal stress on hydrogen absorption into Ni thin film electrodes during alkaline water electrolysis			Type	A1 Journal article
	Year	2020	Publication	Electrochimica Acta	Abbreviated Journal	Electrochim Acta
	Volume	340	Issue		Pages	135970-10
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Efforts to improve the cell efficiency of hydrogen production by water electrolysis continue to address the electrochemical kinetics of the oxygen and hydrogen evolution reactions in detail. The objective of this work is to study a parasitic reaction occurring during the hydrogen evolution reaction (HER), namely the absorption of hydrogen atoms into the bulk electrode. Effects of the electrode microstructure and internal stress on this reaction have been addressed as well in this paper. Ni thin film samples were deposited on a Si substrate by sputter deposition with different deposition pressures, resulting in different microstructures and varying levels of internal stress. These microstructures were first analyzed in detail by Transmission Electron Microscopy (TEM). Cathodic chrono-amperometric measurements and cyclic voltammetries have then been performed in a homemade electrochemical cell. These tests were coupled to a multi-beam optical sensor (MOS) in order to obtain in-situ curvature measurements during hydrogen absorption. Indeed, since hydrogen absorption in the thin film geometry results in a constrained volume expansion, internal stress generation during HER can be monitored by means of curvature measurements. Our results show that different levels of internal stress, grain size and twin boundary density can be obtained by varying the deposition parameters. From an electrochemical point of view, this paper highlights the fact that the electrochemical surface mechanisms during HER are the same for all the electrodes, regardless of their microstructure. However it is shown that the absolute amount of hydrogen being absorbed into the Ni thin films increases when the grain size is reduced, due to a higher grain boundaries density which are favourite absorption sites for hydrogen. At the same time, it was concluded that H-2 evolution is favoured at electrodes having a more compressive (i.e. a less tensile) internal stress. Finally, the subtle effect of microstructure on the hydrogen absorption rate will be discussed as well. (C) 2020 Elsevier Ltd. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000521531800011	Publication Date	2020-02-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0013-4686	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.6	Times cited	2	Open Access	Not_Open_Access
	Notes	; The authors gratefully acknowledge financial support of the Public Service of Wallonia e Department of Energy and Sustainable Building, through the project WallonHY. The ACOM-TEM work was supported by the Hercules Foundation [Grant No. AUHA13009], the Flemish Research Fund (FWO) [Grant No. G.0365.15 N], and the Flemish Strategic Initiative for Materials (SIM) under the project InterPoCo. We also like to cordially thank Ronny Santoro for carrying out the ICP-OES measurements. ;			Approved	Most recent IF: 6.6; 2020 IF: 4.798
	Call Number	UA @ admin @ c:irua:168536			Serial	6497
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	Author	Miotti Bettanini, A.; Ding, L.; Mithieux, J.-D.; Parrens, C.; Idrissi, H.; Schryvers, D.; Delannay, L.; Pardoen, T.; Jacques, P.J.
	Title	Influence of M23C6 dissolution on the kinetics of ferrite to austenite transformation in Fe-11Cr-0.06C stainless steel			Type	A1 Journal article
	Year	2019	Publication	Materials & design	Abbreviated Journal	Mater Design
	Volume	162	Issue		Pages	362-374
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The design of high-strength martensitic stainless steels requires an accurate control over the stability of undesired phases, like carbides and ferrite, which can hamper strength and ductility. Here, the ferrite to austenite transformation in Fe-11Cr-0.06C has been studied with a combined experimental-modelling approach. Experimental observations of the austenization process indicate that austenite growth proceeds in multiple steps, each one characterized by a different transformation rate. DICTRA based modelling reveals that the dissolution of the M23C6 Cr-rich carbides leads to Cr partitioning between austenite and parent phases, which controls the rate of transformation through (i) a soft-impingement effect and (ii) consequent stabilization of the ferrite, which remains untransformed inside chromium-enriched-zones even after prolonged austenization stage. Slow heating rate and smaller initial particle sizes allow the design of ferrite-free microstructure.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000454128400036	Publication Date	2018-12-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0264-1275	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.364	Times cited	3	Open Access	OpenAccess
	Notes	The authors thank Professor Anne-Francoise Gourgues-Lorenzon and Helene Godin, Ecole Nationale Superiore des Mines de Paris (MINES ParisTech) for their fruitful discussions. AMB thanks Stijn Van den broek (Universiteit Antwerpen) for the skillful preparation of TEM samples with FIB. The financial support of CBMM (Companhia Brasileira de Metalurgia e Mineracao) is gratefully acknowledged. L. Delannay is mandated by the FNRS-Belgium. Computational resources have been provided by the supercomputing facilities of the UCLouvain (CISM/UCL) and the Consortium des Equipements de Calcul Intensif en Federation Wallonie Bruxelles (CÉCI) funded by the Fond de la Recherche Scientifique de Belgique (F.R.S.-FNRS) under convention 2.5020.11.; Cbmm; F.r.s.-fnrs, 2.5020.11 ;			Approved	Most recent IF: 4.364
	Call Number	EMAT @ emat @UA @ admin @ c:irua:156721			Serial	5161
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	Author	Jimenez-Mena, N.; Jacques, P.J.; Ding, L.; Gauquelin, N.; Schryvers, D.; Idrissi, H.; Delannay, F.; Simar, A.
	Title	Enhancement of toughness of Al-to-steel Friction Melt Bonded welds via metallic interlayers			Type	A1 Journal article
	Year	2019	Publication	Materials science and engineering: part A: structural materials: properties, microstructure and processing	Abbreviated Journal	Mat Sci Eng A-Struct
	Volume	740-741	Issue		Pages	274-284
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The toughness of Al-to-steel welds decreases with increasing thickness of the intermetallic (IM) layer formed at the interface. Co plating has been added as interlayer in Al-to-steel Friction Melt Bonded (FMB) welds to control the nature and thickness of the IM layer. In comparison to a weld without interlayer, Co plating brings about a reduction of the thickness of the IM layer by 70%. The critical energy release rate of the crack propagating in the weld is used as an indicator of toughness. It is evaluated via an adapted crack propagation test using an energy conservation criterion. For a weld without interlayer, critical energy release rate is found to increase when the thickness of the intermetallic layer decreases. When the intermetallic layer is thick, the crack propagates in a brittle manner through the intermetallic whereas, at low layer thickness, the crack deviates and partially propagates through the Al plate, which causes an increase of toughness. The use of a Co interlayer brings about an increase of toughness by causing full deviation of the crack towards the Al plate.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000453494500029	Publication Date	2018-10-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0921-5093	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.094	Times cited	4	Open Access	Not_Open_Access: Available from 25.10.2020
	Notes	The authors acknowledge the financial support of the Interuniversity Attraction Poles Program from the Belgian State through the Belgian Policy Agency, Belgium, contract IAP7/21 INTEMATE. N. Jimenez-Mena acknowledges the financial support of the (Fonds pour la formation à la recherchedans l'industrie et dans l'agriculture (FRIA), Belgium. A. Simar acknowledges the financial support of the (European Research Council – Starting Grant (ERC-StG), project ALUFIX, grant agreement no 716678. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS), Belgium. The authors also acknowledge M. Coulombier for the help provided in the measurement of the friction coefficient, and T. Pardoen and F. Lani for the fruitful discussions.			Approved	Most recent IF: 3.094
	Call Number	EMAT @ emat @c:irua:154866UA @ admin @ c:irua:154866			Serial	5061
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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	UA @ lucian @ c:irua:94604			Serial	733
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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	UA @ lucian @ c:irua:121086			Serial	2444
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	Author	van der Rest, A.; Idrissi, H.; Henry, F.; Favache, A.; Schryvers, D.; Proost, J.; Raskin, J.-P.; Van Overmeere, Q.; Pardoen, T.
	Title	Mechanical behavior of ultrathin sputter deposited porous amorphous Al2O3 films			Type	A1 Journal article
	Year	2017	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	125	Issue	125	Pages	27-37
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The determination of the mechanical properties of porous amorphous Al2O3 thin films is essential to address reliability issues in wear-resistant, optical and electronic coating applications. Testing the mechanical properties of Al2O3 films thinner than 200 nm is challenging, and the link between the mechanical behavior and the microstructure of such films is largely unknown. Herein, we report on the elastic and viscoplastic mechanical properties of amorphous Al2O3 thin films synthesized by reactive magnetron sputtering using a combination of internal stress, nanoindentation, and on-chip uniaxial tensile testing, together with mechanical homogenization models to separate the effect of porosity from intrinsic variations of the response of the sound material. The porosity is made of voids with 2e30 nm diameter. The Young's modulus and hardness of the films decrease by a factor of two when the deposition pressure increases from 1.2 to 8 mTorr. The contribution of porosity was found to be small, and a change in the atomic structure of the amorphous Al2O3 matrix is hypothesized to be the main contributing factor. The activation volume associated to the viscoplastic deformation mechanism is around 100 Å3. Differences in the atomic structure of the films could not be revealed by electron diffraction, pointing to a minute effect of atomic arrangement on the elastic properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000394201500003	Publication Date	2016-12-02
	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	5	Open Access	OpenAccess
	Notes	This work has been funded by the Belgian Science Policy through the IAP 7/21 project. The support of the ‘Fonds Belge pour la Recherche dans l’Industrie et l’Agriculture (FRIA)’ for A.v.d.R. is also gratefully acknowledged, as well as the support of FNRS through the grant PDR T.0122.13 “Mecano”.			Approved	Most recent IF: 5.301
	Call Number	EMAT @ emat @ c:irua:138990			Serial	4330
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	Author	Idrissi, H.; Béché, A.; Gauquelin, N.; Ul-Haq, I.; Bollinger, C.; Demouchy, S.; Verbeeck, J.; Pardoen, T.; Schryvers, D.; Cordier, P.
	Title	On the formation mechanisms of intragranular shear bands in olivine by stress-induced amorphization			Type	A1 Journal article
	Year	2022	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	239	Issue		Pages	118247-118249
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Intragranular amorphization shear lamellae are found in deformed olivine aggregates. The detailed trans-mission electron microscopy analysis of intragranular lamella arrested in the core of a grain provides novel information on the amorphization mechanism. The deformation field is complex and heteroge-neous, corresponding to a shear crack type instability involving mode I, II and III loading components. The formation and propagation of the amorphous lamella is accompanied by the formation of crystal defects ahead of the tip. These defects are geometrically necessary [001] dislocations, characteristics of high-stress deformation in olivine, and rotational nanodomains which are tentatively interpreted as disclinations. We show that these defects play an important role in dictating the path followed by the amorphous lamella. Stress-induced amorphization in olivine would thus result from a direct crystal-to -amorphous transformation associated with a shear instability and not from a mechanical destabilization due to the accumulation of high number of defects from an intense preliminary deformation. The pref-erential alignment of some lamellae along (010) is a proof of the lower ultimate mechanical strength of these planes.(c) 2022 The Authors. Published by Elsevier Ltd on behalf of Acta Materialia Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000861076600004	Publication Date	2022-08-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1359-6454	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	9.4	Times cited	5	Open Access	OpenAccess
	Notes	The QuanTEM microscope was partially funded by the Flemish government. The K2 camera was funded by FWO Hercules fund G0H4316N 'Direct electron detector for soft matter TEM'. A. Beche acknowledges funding from FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy'). H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). This work was supported by the FNRS under Grant PDR – T011322F and by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme under grant agreement No 787,198 Time Man. J-L Rouviere is acknowledged for his support with the GPA softawre.			Approved	Most recent IF: 9.4
	Call Number	UA @ admin @ c:irua:191432			Serial	7186
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	Author	Schryvers, D.; Cao, S.; Tirry, W.; Idrissi, H.; Van Aert, S.
	Title	Advanced three-dimensional electron microscopy techniques in the quest for better structural and functional materials			Type	A1 Journal article
	Year	2013	Publication	Science and technology of advanced materials	Abbreviated Journal	Sci Technol Adv Mat
	Volume	14	Issue	1	Pages	014206-14213
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	After a short review of electron tomography techniques for materials science, this overview will cover some recent results on different shape memory and nanostructured metallic systems obtained by various three-dimensional (3D) electron imaging techniques. In binary NiTi, the 3D morphology and distribution of Ni4Ti3 precipitates are investigated by using FIB/SEM slice-and-view yielding 3D data stacks. Different quantification techniques will be presented including the principal ellipsoid for a given precipitate, shape classification following a Zingg scheme, particle distribution function, distance transform and water penetration. The latter is a novel approach to quantifying the expected matrix transformation in between the precipitates. The different samples investigated include a single crystal annealed with and without compression yielding layered and autocatalytic precipitation, respectively, and a polycrystal revealing different densities and sizes of the precipitates resulting in a multistage transformation process. Electron tomography was used to understand the interaction between focused ion beam-induced Frank loops and long dislocation structures in nanobeams of Al exhibiting special mechanical behaviour measured by on-chip deposition. Atomic resolution electron tomography is demonstrated on Ag nanoparticles in an Al matrix.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Sendai	Editor
	Language		Wos	000316463800008	Publication Date	2013-03-13
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1468-6996;1878-5514;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.798	Times cited	6	Open Access
	Notes	Fwo; Iap; Esteem			Approved	Most recent IF: 3.798; 2013 IF: 2.613
	Call Number	UA @ lucian @ c:irua:107343			Serial	77
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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	UA @ lucian @ c:irua:133636			Serial	4162
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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	UA @ lucian @ c:irua:114580			Serial	2905
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	Author	Pardoen, T.; Colla, M.-S.; Idrissi, H.; Amin-Ahmadi, B.; Wang, B.; Schryvers, D.; Bhaskar, U.K.; Raskin, J.-P.
	Title	A versatile lab-on-chip test platform to characterize elementary deformation mechanisms and electromechanical couplings in nanoscopic objects			Type	A1 Journal article
	Year	2016	Publication	Comptes rendus : physique	Abbreviated Journal	Cr Phys
	Volume	17	Issue	17	Pages	485-495
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A nanomechanical on-chip test platform has recently been developed to deform under a variety of loading conditions freestanding thin films, ribbons and nanowires involving submicron dimensions. The lab-on-chip involves thousands of elementary test structures from which the elastic modulus, strength, strain hardening, fracture, creep properties can be extracted. The technique is amenable to in situ transmission electron microscopy (TEM) investigations to unravel the fundamental underlying deformation and fracture mechanisms that often lead to size-dependent effects in small-scale samples. The method allows addressing electrical and magnetic couplings as well in order to evaluate the impact of large mechanical stress levels on different solid-state physics phenomena. We had the chance to present this technique in details to Jacques Friedel in 2012 who, unsurprisingly, made a series of critical and very relevant suggestions. In the spirit of his legacy, the paper will address both mechanics of materials related phenomena and couplings with solids state physics issues.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000373524300020	Publication Date	2015-12-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1631-0705	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.048	Times cited	7	Open Access
	Notes	This research has been performed with the financial support of the “Politique scientifique fédérale” under the framework of the interuniversity attraction poles program, IAP7/21, as well as with the support of the “Communauté française de Belgique” under the program “Actions de recherche concertées” ARC 05/10-330 and ARC Convention No. 11/16-037. The support of the “Fonds belge pour la recherche dans l'industrie et l'agriculture (FRIA)” for M.-S. Colla is also gratefully acknowledged as are the FWO research projects G012012N “Understanding nanocrystalline mechanical behavior from structural investigations” for B. Amin-Ahmadi.			Approved	Most recent IF: 2.048
	Call Number	c:irua:129995			Serial	4014
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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	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.
	Address
	Corporate Author				Thesis
	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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	Author	Samaee, V.; Gatti, R.; Devincre, B.; Pardoen, T.; Schryvers, D.; Idrissi, H.
	Title	Dislocation driven nanosample plasticity: new insights from quantitative in-situ TEM tensile testing			Type	A1 Journal Article
	Year	2018	Publication	Scientific Reports	Abbreviated Journal	Sci Rep-Uk
	Volume	8	Issue	1	Pages	12012
	Keywords	A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
	Abstract	Intrinsic dislocation mechanisms in the vicinity of free surfaces of an almost FIB damage-free single crystal Ni sample have been quantitatively investigated owing to a novel sample preparation method combining twin-jet electro-polishing, in-situ TEM heating and FIB. The results reveal that the small-scale plasticity is mainly controlled by the conversion of few tangled dislocations, still present after heating, into stable single arm sources (SASs) as well as by the successive operation of these sources. Strain hardening resulting from the operation of an individual SAS is reported and attributed to the decrease of the length of the source. Moreover, the impact of the shortening of the dislocation source on the intermittent plastic flow, characteristic of SASs, is discussed. These findings provide essential information for the understanding of the regime of ‘dislocation source’ controlled plasticity and the related mechanical size effect.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000460200900001	Publication Date	2018-08-07
	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	9	Open Access	Not_Open_Access
	Notes	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.014.13 N and SCHW855/5-1, respectively, is gratefully acknowledged. V. Samaee also acknowledges the FWO research project G012012N “Understanding nanocrystalline mechanical behaviour from structural investigations”. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). Dr. Ruth Schwaiger is acknowledged for providing the Ni foils used to prepare the in-situ TEM tensile specimens.			Approved	Most recent IF: 4.259
	Call Number	EMAT @ emat @c:irua:155772			Serial	5136
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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	UA @ lucian @ c:irua:114782			Serial	1614
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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.
	Address
	Corporate Author				Thesis
	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.
	Address
	Corporate Author				Thesis
	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	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	UA @ lucian @ c:irua:97391			Serial	2239
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	Author	Amin-Ahmadi, B.; Idrissi, H.; Galceran, M.; Colla, M.S.; Raskin, J.P.; Pardoen, T.; Godet, S.; Schryvers, D.
	Title	Effect of deposition rate on the microstructure of electron beam evaporated nanocrystalline palladium thin films			Type	A1 Journal article
	Year	2013	Publication	Thin solid films : an international journal on the science and technology of thin and thick films	Abbreviated Journal	Thin Solid Films
	Volume	539	Issue		Pages	145-150
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The influence of the deposition rate on the formation of growth twins in nanocrystalline Pd films deposited by electron beam evaporation is investigated using transmission electron microscopy. Statistical measurements prove that twin boundary (TB) density and volume fraction of grains containing twins increase with increasing deposition rate. A clear increase of the dislocation density was observed for the highest deposition rate of 5 Å/s, caused by the increase of the internal stress building up during deposition. Based on crystallographic orientation indexation using transmission electron microscopy, it can be concluded that a {111} crystallographic texture increases with increasing deposition rate even though the {101} crystallographic texture remains dominant. Most of the TBs are fully coherent without any residual dislocations. However, for the highest deposition rate (5 Å/s), the coherency of the TBs decreases significantly as a result of the interaction of lattice dislocations emitted during deposition with the growth TBs. The analysis of the grain boundary character of different Pd films shows that an increasing fraction of high angle grain boundaries with misorientation angles around 5565° leads to a higher potential for twin formation.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lausanne	Editor
	Language		Wos	000321111100025	Publication Date	2013-05-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0040-6090;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	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.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000355884300012	Publication Date	2015-05-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0360-3199;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.582	Times cited	13	Open Access
	Notes	Iap 7/21			Approved	Most recent IF: 3.582; 2015 IF: 3.313
	Call Number	c:irua:126429			Serial	838
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	Author	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]
	Address
	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.
	Address
	Corporate Author				Thesis
	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	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	UA @ lucian @ c:irua:112815			Serial	3478
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