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	Author	Bagherpour, A.; Baral, P.; Colla, M.-S.; Orekhov, A.; Idrissi, H.; Haye, E.; Pardoen, T.; Lucas, S.
	Title	Tailoring Mechanical Properties of a-C:H:Cr Coatings			Type	A1 Journal Article
	Year	2023	Publication	Coatings	Abbreviated Journal	Coatings
	Volume	13	Issue	12	Pages	2084
	Keywords	A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
	Abstract	The development of coatings with tunable performances is critical to meet a wide range of technological applications each one with different requirements. Using the plasma-enhanced chemical vapor deposition (PECVD) process, scientists can create hydrogenated amorphous carbon coatings doped with metal (a-C:H:Me) with a broad range of mechanical properties, varying from those resembling polymers to ones resembling diamond. These diverse properties, without clear relations between the different families, make the material selection and optimization difficult but also very rich. An innovative approach is proposed here based on projected performance indices related to fracture energy, strength, and stiffness in order to classify and optimize a-C:H:Me coatings. Four different a-C:H:Cr coatings deposited by PECVD with Ar/C2H2 discharge under different bias voltage and pressures are investigated. A path is found to produce coatings with a selective critical energy release rate between 5–125 J/m2 without compromising yield strength (1.6–2.7 GPa) and elastic limit (≈0.05). Finally, fine-tuned coatings are categorized to meet desired applications under different testing conditions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001136013600001	Publication Date	2023-12-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2079-6412	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor		Times cited		Open Access
	Notes	Walloon region under the PDR FNRS, C 62/5—PDR/OL 33677636 ; Belgian National Fund for Scientific Research, CDR—J.0113.20 ; National Fund for Scientific Reaserch;			Approved	Most recent IF: NA
	Call Number	EMAT @ emat @c:irua:202390			Serial	8982
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	Author	Krishnamurthy, S.C.; Arseenko, M.; Kashiwar, A.; Dufour, P.; Marchal, Y.; Delahaye, J.; Idrissi, H.; Pardoen, T.; Mertens, A.; Simar, A.
	Title	Controlled precipitation in a new Al-Mg-Sc alloy for enhanced corrosion behavior while maintaining the mechanical performance			Type	A1 Journal article
	Year	2023	Publication	Materials characterization	Abbreviated Journal
	Volume	200	Issue		Pages	112886-11
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The hot working of 5xxx series alloys with Mg ≥3.5 wt% is a concern due to the precipitation of β (Al3Mg2) phase at grain boundaries favoring Inter Granular Corrosion (IGC). The mechanical and corrosion properties of a new 5028-H116 Al-Mg-Sc alloy under various β precipitates distribution is analyzed by imposing different cooling rates from the hot forming temperature (i.e. 325 °C). The mechanical properties are maintained regardless of the heat treatment. However, the different nucleation sites and volume fractions of β precipitates for different cooling rates critically affect IGC. Controlled furnace cooling after the 325 °C heat treatment is ideal in 5028-H116 alloy to reduce susceptibility to IGC after sensitization.
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000977059100001	Publication Date	2023-04-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1044-5803	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.7	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 4.7; 2023 IF: 2.714
	Call Number	UA @ admin @ c:irua:195598			Serial	7291
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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/ )
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	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	Bignoli, F.; Rashid, S.; Rossi, E.; Jaddi, S.; Djemia, P.; Terraneo, G.; Li Bassi, A.; Idrissi, H.; Pardoen, T.; Sebastiani, M.; Ghidelli, M.
	Title	Effect of annealing on mechanical properties and thermal stability of ZrCu/O nanocomposite amorphous films synthetized by pulsed laser deposition			Type	A1 Journal article
	Year	2022	Publication	Materials & design	Abbreviated Journal	Mater Design
	Volume	221	Issue		Pages	110972-10
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Binary ZrCu nanocomposite amorphous films are synthetized by pulsed laser deposition (PLD) under vac-uum (2 x 10-3 Pa) and 10 Pa He pressure, leading to fully amorphous compact and nanogranular mor-phologies, respectively. Then, post-thermal annealing treatments are carried out to explore thermal stability and crystallization phenomena together with the evolution of mechanical properties. Compact films exhibit larger thermal stability with partial crystallization phenomena starting at 420 degrees C, still to be completed at 550 degrees C, while nanogranular films exhibit early-stage crystallization at 300 degrees C and com-pleted at 485 degrees C. The microstructural differences are related to a distinct evolution of mechanical
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000886072100004	Publication Date	2022-07-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0264-1275; 1873-4197	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.4	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 8.4
	Call Number	UA @ admin @ c:irua:192194			Serial	7299
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	Author	Baral, P.; Orekhov, A.; Dohmen, R.; Coulombier, M.; Raskin, J.P.; Cordier, P.; Idrissi, H.; Pardoen, T.
	Title	Rheology of amorphous olivine thin films characterized by nanoindentation			Type	A1 Journal article
	Year	2021	Publication	Acta Materialia	Abbreviated Journal	Acta Mater
	Volume	219	Issue		Pages	117257
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The rheological properties of amorphous olivine thin films deposited by pulsed laser deposition have been studied based on ambient temperature nanoindentation under constant strain-rate as well as re-laxation conditions. The amorphous olivine films exhibit a viscoelastic-viscoplastic behavior with a significant rate dependency. The strain-rate sensitivity m is equal to similar to 0 . 05 which is very high for silicates, indicating a complex out-of-equilibrium structure. The minimum apparent activation volume determined from nanoindentation experiments corresponds to Mg and Fe atomic metallic sites in the (Mg,Fe)(2)SiO4 crystalline lattice. The ambient temperature creep behavior of the amorphous olivine films differs very much from the one of single crystal olivine. This behavior directly connects to the recent demonstration of the activation of grain boundary sliding in polycrystalline olivine following grain boundary amorphization under high-stress. (C) 2021 The Authors. Published by Elsevier Ltd on behalf of Acta Materialia Inc.
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000706867800004	Publication Date	2021-08-19
	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		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 5.301
	Call Number	UA @ admin @ c:irua:182592			Serial	6882
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	Author	Ghidelli, M.; Orekhov, A.; Bassi, A.L.; Terraneo, G.; Djemia, P.; Abadias, G.; Nord, M.; Béché, A.; Gauquelin, N.; Verbeeck, J.; Raskin, J.-p.; Schryvers, D.; Pardoen, T.; Idrissi, H.
	Title	Novel class of nanostructured metallic glass films with superior and tunable mechanical properties			Type	A1 Journal article
	Year	2021	Publication	Acta Materialia	Abbreviated Journal	Acta Mater
	Volume		Issue		Pages	116955
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	A novel class of nanostructured Zr50Cu50 (%at.) metallic glass films with superior and tunable mechanical properties is produced by pulsed laser deposition. The process can be controlled to synthetize a wide range of film microstructures including dense fully amorphous, amorphous embedded with nanocrystals and amorphous nano-granular. A unique dense self-assembled nano-laminated atomic arrangement characterized by alternating Cu-rich and Zr/O-rich nanolayers with different local chemical enrichment and amorphous or amorphous-crystalline composite nanostructure has been discovered, while significant in-plane clustering is reported for films synthetized at high deposition pressures. This unique nanoarchitecture is at the basis of superior mechanical properties including large hardness and elastic modulus up to 10 and 140 GPa, respectively and outstanding total elongation to failure (>9%), leading to excellent strength/ductility balance, which can be tuned by playing with the film architecture. These results pave the way to the synthesis of novel class of engineered nanostructured metallic glass films with high structural performances attractive for a number of applications in microelectronics and coating industry.
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000670077800004	Publication Date	2021-05-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1359-6454	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.301	Times cited	27	Open Access	OpenAccess
	Notes	H.I. is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). This work was supported by the Fonds de la Recherche Scientifique – FNRS under Grant T.0178.19 and Grant CDR– J011320F. We acknowledge funding for the direct electron detector used in the 4D stem studies from the Hercules fund 'Direct electron detector for soft matter TEM' from the Flemish Government J.V acknowledges funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 823717 – ESTEEM3. A.O. has received partial funding from the GOA project “Solarpaint” of the University of Antwerp. A.B. and J.V. acknowledge funding through FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund. M.G. and A.L.B acknowledge Chantelle Ekanem for support in PLD depositions.			Approved	Most recent IF: 5.301
	Call Number	EMAT @ emat @c:irua:178142			Serial	6761
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	Author	Samaee, V.; Dupraz, M.; Pardoen, T.; VAn Swygenhoven, H.; Schryvers, D.; Idrissi, H.
	Title	Deciphering the interactions between single arm dislocation sources and coherent twin boundary in nickel bi-crystal			Type	A1 Journal article
	Year	2021	Publication	Nature Communications	Abbreviated Journal	Nat Commun
	Volume	12	Issue	1	Pages	962
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The introduction of a well-controlled population of coherent twin boundaries (CTBs) is an attractive route to improve the strength ductility product in face centered cubic (FCC) metals. However, the elementary mechanisms controlling the interaction between single arm dislocation sources (SASs), often present in nanotwinned FCC metals, and CTB are still not well understood. Here, quantitative in-situ transmission electron microscopy (TEM) observations of these mechanisms under tensile loading are performed on submicron Ni bi-crystal. We report that the absorption of curved screw dislocations at the CTB leads to the formation of constriction nodes connecting pairs of twinning dislocations at the CTB plane in agreement with large scale 3D atomistic simulations. The coordinated motion of the twinning dislocation pairs due to the presence of the nodes leads to a unique CTB sliding mechanism, which plays an important role in initiating the fracture process at a CTB ledge. TEM observations of the interactions between non-screw dislocations and the CTB highlight the importance of the synergy between the repulsive force of the CTB and the back stress from SASs when the interactions occur in small volumes. Interactions of dislocations with coherent twin boundaries contribute to strength and ductility in metals, but investigating the interaction mechanisms is challenging. Here the authors unravel these mechanisms through quantitative in-situ transmission electron microscopy observations in nickel bi-crystal samples under tensile loading.
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000620142700024	Publication Date	2021-02-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2041-1723	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	12.124	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 12.124
	Call Number	UA @ admin @ c:irua:176680			Serial	6722
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	Author	Bahrami, F.; Hammad, M.; Fivel, M.; Huet, B.; D'Haese, C.; Ding, L.; Nysten, B.; Idrissi, H.; Raskin, J.P.; Pardoen, T.
	Title	Single layer graphene controlled surface and bulk indentation plasticity in copper			Type	A1 Journal article
	Year	2021	Publication	International Journal Of Plasticity	Abbreviated Journal	Int J Plasticity
	Volume	138	Issue		Pages	102936
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The impact of graphene reinforcement on the mechanical properties of metals has been a subject of intense investigation over the last decade in surface applications to mitigate the impact of tribological loadings or for strengthening purposes when dispersed into a bulk material. Here, the effect on the plastic indentation response of a single graphene layer grown on copper is analyzed for two configurations: one with graphene at the surface, the other with graphene sandwiched under a 100 nm thick copper cap layer. Nanoindentation under both displacement and load control conditions show both earlier and shorter pop-in excursions compared to systems without graphene. Atomic force microscopy reveals much smoother pile-ups with no slip traces in the presence of a surface graphene layer. The configuration with the intercalated graphene layer appears as an ideal elementary system to address bulk hardening mechanisms by indentation testing. Transmission electron microscopy (TEM) cross-sections below indents show more diffuse and homogeneous dislocation activity in the presence of graphene. 3D dislocation dynamics simulations allow unraveling of the origin of these 3D complex phenomena and prove that the collective dislocation mechanisms are dominantly controlled by the strong back stress caused by the graphene barrier. These results provide a quantitative understanding of the impact of graphene on dislocation mechanisms for both surface and bulk applications, but with an impact that is not as large as anticipated from other studies or general literature claims.
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000623869800001	Publication Date	2021-01-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0749-6419	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.702	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 5.702
	Call Number	UA @ admin @ c:irua:176729			Serial	6735
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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.; Samaee, V.; Lumbeeck, G.; Werf, T.; Pardoen, T.; Schryvers, D.; Cordier, P.
	Title	In Situ Quantitative Tensile Testing of Antigorite in a Transmission Electron Microscope			Type	A1 Journal article
	Year	2020	Publication	Journal Of Geophysical Research-Solid Earth	Abbreviated Journal	J Geophys Res-Sol Ea
	Volume	125	Issue	3	Pages
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The determination of the mechanical properties of serpentinites is essential toward the understanding of the mechanics of faulting and subduction. Here we present the first in situ tensile tests on antigorite in a transmission electron microscope. A push‐to‐pull deformation device is used to perform quantitative tensile tests, during which force and displacement are measured, while the evolving microstructure is imaged with the microscope. The experiments have been performed at room temperature on 2 × 1 × 0.2 μm3 beams prepared by focused ion beam. The specimens are not single crystals despite their small sizes. Orientation mapping indicated that several grains were well oriented for plastic slip. However, no dislocation activity has been observed even though the engineering tensile stress went up to 700 MPa. We show also that antigorite does not exhibit a purely elastic‐brittle behavior since, despite the presence of defects, the specimens accumulate permanent deformation and did not fail within the elastic regime. Instead, we observe that strain localizes at grain boundaries. All observations concur to show that under these experimental conditions, grain boundary sliding is the dominant deformation mechanism. This study sheds a new light on the mechanical properties of antigorite and calls for further studies on the structure and properties of grain boundaries in antigorite and more generally in phyllosilicates.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000530895800023	Publication Date	2020-02-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2169-9313	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.9	Times cited		Open Access	OpenAccess
	Notes	We thank S. Guillot for having kindly provided us with the two antigorite samples investigated in this study. We acknowledge funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program under Grant Agreement 787198—TimeMan. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR‐FNRS). We acknowledge fruitful discussions with A. Baronnet. We thank J. Gasc and an anonymous reviewer for their critical comments. Data (movies of the three in situ deformation experiments) can be downloaded (from https://doi.org/10.5281/zenodo.3583135).			Approved	Most recent IF: 3.9; 2020 IF: 3.35
	Call Number	EMAT @ emat @c:irua:167594			Serial	6355
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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	Sandfeld, S.; Samaee, V.; Idrissi, H.; Groten, J.; Pardoen, T.; Schwaiger, R.; Schryvers, D.
	Title	Datasets for the analysis of dislocations at grain boundaries and during vein formation in cyclically deformed Ni micropillars			Type	A1 Journal article
	Year	2019	Publication	Data in Brief	Abbreviated Journal
	Volume	27	Issue	27	Pages	104724
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The dataset together with the corresponding Python scripts and Jupyter notebooks presented in this article are supplementary data for the work presented in Samaee et al., 2019 [1]. The data itself consists of two parts: the simulation data that was used in [1] to analyze the effect of a particular grain boundary on curved dislocations and the precession electron diffraction (PED) strain maps together with post-processed data for analyzing details of the observed dislocation vein structures. Additionally, the complete stress tensor components, which are not shown in [1], have also been included. The data sets are accompanied by Python code explaining the file formats and showing how to post-process the data. (c) 2019 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000501988200181	Publication Date	2019-11-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2352-3409	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:165092			Serial	6292
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	Author	Idrissi, H.; Ghidelli, M.; Béché, A.; Turner, S.; Gravier, S.; Blandin, J.-J.; Raskin, J.-P.; Schryvers, D.; Pardoen, T.
	Title	Atomic-scale viscoplasticity mechanisms revealed in high ductility metallic glass films			Type	A1 Journal article
	Year	2019	Publication	Scientific reports	Abbreviated Journal	Sci Rep-Uk
	Volume	9	Issue	1	Pages	13426
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The fundamental plasticity mechanisms in thin freestanding Zr65Ni35 metallic glass films are investigated in order to unravel the origin of an outstanding strength/ductility balance. The deformation process is homogenous until fracture with no evidence of catastrophic shear banding. The creep/relaxation behaviour of the films was characterized by on-chip tensile testing, revealing an activation volume in the range 100–200 Å3. Advanced high-resolution transmission electron microscopy imaging and spectroscopy exhibit a very fine glassy nanostructure with well-defined dense Ni-rich clusters embedded in Zr-rich clusters of lower atomic density and a ~2–3 nm characteristic length scale. Nanobeam electron diffraction analysis reveals that the accumulation of plastic deformation at roomtemperature correlates with monotonously increasing disruption of the local atomic order. These results provide experimental evidences of the dynamics of shear transformation zones activation in metallic glasses. The impact of the nanoscale structural heterogeneities on the mechanical properties including the rate dependent behaviour is discussed, shedding new light on the governing plasticity mechanisms in metallic glasses with initially heterogeneous atomic arrangement.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000486139700008	Publication Date	2019-09-17
	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		Open Access
	Notes	H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). This work was supported by the FNRS under Grant PDR – T.0178.19. FWO project G093417N (‘Compressed sensing enabling low dose imaging in transmission electron microscopy’) and Hercules fund ‘Direct electron detector for soft matter TEM’ from Flemish Government are acknowledged.			Approved	Most recent IF: 4.259
	Call Number	EMAT @ emat @c:irua:162786			Serial	5375
Permanent link to this record



	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
Permanent link to this record



	Author	Idrissi, H.; Samaee, V.; Lumbeeck, G.; van der Werf, T.; Pardoen, T.; Schryvers, D.; Cordier, P.
	Title	Supporting data for “In situ Quantitative Tensile Tests on Antigorite in a Transmission Electron Microscope”			Type	Dataset
	Year	2019	Publication		Abbreviated Journal
	Volume		Issue		Pages
	Keywords	Dataset; Electron microscopy for materials research (EMAT)
	Abstract	The determination of the mechanical properties of serpentinites is essential towards the understanding of the mechanics of faulting and subduction. Here, we present the first in situ tensile tests on antigorite in a transmission electron microscope. A push-to-pull deformation device is used to perform quantitative tensile tests, during which force and displacement are measured, while the microstructure is imaged with the microscope. The experiments have been performed at room temperature on beams prepared by focused ion beam. The specimens are not single crystals despite their small sizes. Orientation mapping indicated that some grains were well-oriented for plastic slip. However, no dislocation activity has been observed even though engineering tensile stress went up to 700 MPa. We show also that antigorite does not exhibit an pure elastic-brittle behaviour since, despite the presence of defects, the specimens underwent plastic deformation and did not fail within the elastic regime. Instead, we observe that strain localizes at grain boundaries. All observations concur to show that under our experimental conditions, grain boundary sliding is the dominant deformation mechanism. This study sheds a new light on the mechanical properties of antigorite and calls for further studies on the structure and properties of grain boundaries in antigorite and more generally in phyllosilicates.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:169107			Serial	6891
Permanent link to this record



	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	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	Ghidelli, M.; Idrissi, H.; Gravier, S.; Blandin, J.-J.; Raskin, J.-P.; Schryvers, D.; Pardoen, T.
	Title	Homogeneous flow and size dependent mechanical behavior in highly ductile Zr 65 Ni 35 metallic glass films			Type	A1 Journal article
	Year	2017	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	131	Issue	131	Pages	246-259
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Motivated by recent studies demonstrating a high strength – high ductility potential of nano-scale metallic glass samples, the mechanical response of freestanding Zr65Ni35 film with sub-micron thickness has been investigated by combining advanced on-chip tensile testing and electron microscopy. Large deformation up to 15% is found for specimen thicknesses below 500 nm with variations depending on specimen size and frame compliance. The deformation is homogenous until fracture, with no evidence of shear banding. The yield stress is doubled when decreasing the specimen cross-section, reaching ~3 GPa for small cross-sections. The fracture strain variation is related to both the stability of the test device and to the specimen size. The study concludes on clear disconnect between the mechanisms controlling the onset of plasticity and the fracture process.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000402343400023	Publication Date	2017-03-31
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1359-6454	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.301	Times cited	42	Open Access	OpenAccess
	Notes	This work has been funded by the Belgian Science Policy through the IAP 7/21 project. We acknowledge IDS-FunMat for the PhD financial support.We thank the Renatech network and the PTA (Plateforme Technologique Amont) in Grenoble (France) for TFMG deposition facilities. The WINFAB infrastructure at the UCL and the help of R. Vayrette and M. Coulombier for the on-chip tests. H. Idrissi is currently mandated by the Belgian National Fund for Scientific Research (FSR-FNRS).			Approved	Most recent IF: 5.301
	Call Number	EMAT @ emat @ c:irua:142642			Serial	4562
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	Author	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
Permanent link to this record



	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
Permanent link to this record



	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
Permanent link to this record



	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
Permanent link to this record



	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	Colla, M.-S.; Amin-Ahmadi, B.; Idrissi, H.; Malet, L.; Godet, S.; Raskin, J.-P.; Schryvers, D.; Pardoen, T.
	Title	Dislocation-mediated relaxation in nanograined columnar palladium films revealed by on-chip time-resolved HRTEM testing			Type	A1 Journal article
	Year	2015	Publication	Nature communications	Abbreviated Journal	Nat Commun
	Volume	6	Issue	6	Pages	5922
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The high-rate sensitivity of nanostructured metallic materials demonstrated in the recent literature is related to the predominance of thermally activated deformation mechanisms favoured by a large density of internal interfaces. Here we report time-resolved high-resolution electron transmission microscopy creep tests on thin nanograined films using on-chip nanomechanical testing. Tests are performed on palladium, which exhibited unexpectedly large creep rates at room temperature. Despite the small 30-nm grain size, relaxation is found to be mediated by dislocation mechanisms. The dislocations interact with the growth nanotwins present in the grains, leading to a loss of coherency of twin boundaries. The density of stored dislocations first increases with applied deformation, and then decreases with time to drive additional deformation while no grain boundary mechanism is observed. This fast relaxation constitutes a key issue in the development of various micro- and nanotechnologies such as palladium membranes for hydrogen applications.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000348742300002	Publication Date	2015-01-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2041-1723;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	12.124	Times cited	34	Open Access
	Notes	Iap7/21; Fwo G012012n			Approved	Most recent IF: 12.124; 2015 IF: 11.470
	Call Number	c:irua:122045			Serial	731
Permanent link to this record



	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	UA @ lucian @ c:irua:116866			Serial	2649
Permanent link to this record



	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	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	Wang, B.; Idrissi, H.; Galceran, M.; Colla, M.S.; Turner, S.; Hui, S.; Raskin, J.P.; Pardoen, T.; Godet, S.; Schryvers, D.
	Title	Advanced TEM investigation of the plasticity mechanisms in nanocrystalline freestanding palladium films with nanoscale twins			Type	A1 Journal article
	Year	2012	Publication	International journal of plasticity	Abbreviated Journal	Int J Plasticity
	Volume	37	Issue		Pages	140-156
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Nanocrystalline palladium thin films deposited by electron-beam evaporation and deformed by on-chip tensile testing reveal a surprisingly large strain hardening capacity when considering the small similar to 25 nm grain size. The as-grown films contain several coherent single and multifold twin boundaries. The coherency of the twin boundaries considerably decreases with deformation due to dislocation/twin boundary interactions. These reactions are described based on a detailed analysis of the number and the type of dislocations located at the twin boundaries using high-resolution TEM, including aberration corrected microscopy. Sessile Frank dislocations were observed at the twin/matrix interfaces, explaining the loss of the TB coherency due to the Burgers vector pointing out of the twinning plane. Grain boundary mediated processes were excluded as a mechanism dominating the plastic deformation based on the investigation of the grain size distribution as well as the crystallographic texture using Automated Crystallographic Orientation Indexation TEM. Other factors influencing the plastic deformation such as impurities and the presence of a native passivation oxide layer at the surface of the films were investigated using analytical TEM. The twin boundaries observed in the present work partly explain the high strain hardening capacity by providing both increasing resistance to dislocation motion with deformation and a source for dislocation multiplication. (C) 2012 Elsevier Ltd. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000307416100009	Publication Date	2012-05-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0749-6419;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.702	Times cited	44	Open Access
	Notes	Iap; Fwo			Approved	Most recent IF: 5.702; 2012 IF: 4.356
	Call Number	UA @ lucian @ c:irua:101082			Serial	74
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	Author	Colla, M.-S.; Wang, B.; Idrissi, H.; Schryvers, D.; Raskin, J.-P.; Pardoen, T.
	Title	High strength-ductility of thin nanocrystalline palladium films with nanoscale twins : on-chip testing and grain aggregate model			Type	A1 Journal article
	Year	2012	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	60	Issue	4	Pages	1795-1806
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The mechanical behaviour of thin nanocrystalline palladium films with an ∼30 nm in plane grain size has been characterized on chip under uniaxial tension. The films exhibit a large strain hardening capacity and a significant increase in the strength with decreasing thickness. Transmission electron microscopy has revealed the presence of a moderate density of growth nanotwins interacting with dislocations. A semi-analytical grain aggregate model is proposed to investigate the impact of different contributions to the flow behaviour, involving the effect of twins, of grain size and of the presence of a thin surface layer. This model provides guidelines to optimizing the strength/ductility ratio of the films.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000301989500035	Publication Date	2012-02-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1359-6454;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.301	Times cited	38	Open Access
	Notes	Iap			Approved	Most recent IF: 5.301; 2012 IF: 3.941
	Call Number	UA @ lucian @ c:irua:94213			Serial	1465
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	Author	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	UA @ lucian @ c:irua:96955			Serial	3566
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