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Author | Brognara, A.; Kashiwar, A.; Jung, C.; Zhang, X.; Ahmadian, A.; Gauquelin, N.; Verbeeck, J.; Djemia, P.; Faurie, D.; Dehm, G.; Idrissi, H.; Best, J.P.; Ghidelli, M. | ||||
Title | Tailoring mechanical properties and shear band propagation in ZrCu metallic glass nanolaminates through chemical heterogeneities and interface density | Type | A1 Journal article | ||
Year | 2024 | Publication | Small Structures | Abbreviated Journal | |
Volume | Issue | Pages | 2400011-11 | ||
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The design of high‐performance structural thin films consistently seeks to achieve a delicate equilibrium by balancing outstanding mechanical properties like yield strength, ductility, and substrate adhesion, which are often mutually exclusive. Metallic glasses (MGs) with their amorphous structure have superior strength, but usually poor ductility with catastrophic failure induced by shear bands (SBs) formation. Herein, we introduce an innovative approach by synthesizing MGs characterized by large and tunable mechanical properties, pioneering a nanoengineering design based on the control of nanoscale chemical/structural heterogeneities. This is realized through a simplified model Zr 24 Cu 76 /Zr 61 Cu 39 , fully amorphous nanocomposite with controlled nanoscale periodicity ( Λ , from 400 down to 5 nm), local chemistry, and glass–glass interfaces, while focusing in‐depth on the SB nucleation/propagation processes. The nanolaminates enable a fine control of the mechanical properties, and an onset of crack formation/percolation (>1.9 and 3.3%, respectively) far above the monolithic counterparts. Moreover, we show that SB propagation induces large chemical intermixing, enabling a brittle‐to‐ductile transition when Λ ≤ 50 nm, reaching remarkably large plastic deformation of 16% in compression and yield strength ≈2 GPa. Overall, the nanoengineered control of local heterogeneities leads to ultimate and tunable mechanical properties opening up a new approach for strong and ductile materials. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2024-05-20 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2688-4062 | ISBN | Additional Links | UA library record | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ admin @ c:irua:205798 | Serial | 9176 | ||
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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. | ||||
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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 | Ding, L.; Zhao, L.; Weng, Y.; Schryvers, D.; Liu, Q.; Idrissi, H. | ||||
Title | Atomic-scale investigation of the heterogeneous precipitation in the E (Al₁₈Mg₃Cr₂) dispersoid of 7075 aluminum alloy | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Alloys And Compounds | Abbreviated Journal | J Alloy Compd |
Volume | 851 | Issue | Pages | 156890 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The heterogeneous precipitation of the eta (MgZn2) phase on the E (Al18Mg3Cr2) dispersoids of the 7075 aluminum alloy was systematically investigated by atomic resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and energy dispersive X-ray spectrometry (EDX). It is found that coarse B particles are heterogeneously precipitated at the E particle interface after water quenching and isothermal aging at 120 degrees C. The incoherent E/Al interface is responsible for the high tendency of heterogeneous precipitation of the B phase. Two different orientation relationships (ORs) between the eta, E and Al matrix are identified: OR1 [2 (11) over bar0](eta)[011](E)//[(1) over bar 12](Al), (01 (1) over bar0)(eta)//(13 (3) over bar)(E)//(201)(Al), OR2 [(1) over bar 12](E)//[0001](eta)//[011](Al), (01 (1) over bar0 )(eta)//(220)(E)//(34 (4) over bar)(Al). The eta phase is preferential to nucleate along the {111}(E) or the {220}(E) planes, depending on its OR. The heterogeneous nucleation of B phase on the E particle could stabilize the E/Al interface by introducing a coherent E/eta interface, which increases the drive force of heterogeneous precipitation. The reorientation of eta phase and mutual diffusion of solute atoms could assist the coherency of the E/eta interface. The present results suggest that increasing the coherency of the E/Al interface is a promising method to suppress the heterogeneous precipitation of the eta phase. (C) 2020 Elsevier B.V. All rights reserved. | ||||
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Language | Wos | 000579868900103 | Publication Date | 2020-08-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0925-8388 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.133 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 3.133 | |||
Call Number | UA @ admin @ c:irua:173503 | Serial | 6717 | ||
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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. | ||||
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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. | ||||
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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 | Lumbeeck, G.; Delvaux, A.; Idrissi, H.; Proost, J.; Schryvers, D. | ||||
Title | Analysis of internal stress build-up during deposition of nanocrystalline Ni thin films using transmission electron microscopy | Type | A1 Journal article | ||
Year | 2020 | Publication | Thin solid films : an international journal on the science and technology of thin and thick films | Abbreviated Journal | Thin Solid Films |
Volume | 707 | Issue | Pages | 138076 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Ni thin films sputter-deposited at room temperature with varying Ar pressures were investigated with automated crystal orientation mapping in a transmission electron microscope to uncover the mechanisms controlling the internal stress build-up recorded in-situ during deposition. Large grains were found to induce behaviour similar to a stress-free nucleation layer. The measurements of grain size in most of the Ni thin films are in agreement with the island coalescence model. Low internal stress was observed at low Ar pressure and was explained by the presence of large grains. Relaxation of high internal stress was also noticed at the highest Ar pressure, which was attributed to a decrease of Σ3 twin boundary density due to a low deposition rate. The results provide insightful information to better understand the relationship between structural boundaries and the evolution of internal stress upon deposition of thin films. | ||||
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Language | Wos | 000539312200011 | Publication Date | 2020-05-12 | |
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ISSN | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | ||
Impact Factor | Times cited | Open Access | OpenAccess | ||
Notes | This work was supported by the Hercules Foundation [Grant No. AUHA13009], the Flemish Research Fund (FWO) [Grant No. G.0365.15N], and the Flemish Strategic Initiative for Materials (SIM) under the project InterPoCo. Thin film deposition has been realised as part of the WallonHY project, funded by the Public Service of Wallonia – Department of Energy and Sustainable Building. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). | Approved | Most recent IF: NA | ||
Call Number | EMAT @ emat @c:irua:169708 | Serial | 6370 | ||
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Author | 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. | ||||
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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 | Salje, E.K.H.; Zhang, H.; Idrissi, H.; Schryvers, D.; Carpenter, M.A.; Moya, X.; Planes, A. | ||||
Title | Mechanical resonance of the austenite/martensite interface and the pinning of the martensitic microstructures by dislocations in Cu74.08Al23.13Be2.79 | Type | A1 Journal article | ||
Year | 2009 | Publication | Physical review: B: condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 80 | Issue | 13 | Pages | 134114,1-1134114,8 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A single crystal of Cu74.08Al23.13Be2.79 undergoes a martensitic phase transition at 246 and 232 K under heating and cooling, respectively. The phase fronts between the austenite and martensite regions of the sample are weakly mobile with a power-law resonance under external stress fields. Surprisingly, the martensite phase is elastically much harder than the austenite phase showing that interfaces between various crystallographic variants are strongly pinned and cannot be moved by external stress while the phase boundary between the austenite and martensite regions in the sample remains mobile. This unusual behavior was studied by dynamical mechanical analysis (DMA) and resonant ultrasound spectroscopy. The remnant strain, storage modulus, and internal friction were recorded simultaneously for different applied forces in DMA. With increasing forces, the remnant strain increases monotonously while the internal friction peak height shows a minimum at 300 mN. Transmission electron microscopy shows that the pinning is generated by dislocations which are inherited from the austenite phase. | ||||
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Publisher | Place of Publication | Lancaster, Pa | Editor | ||
Language | Wos | 000271351300033 | Publication Date | 2009-10-22 | |
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 38 | Open Access | |
Notes | Multimat | Approved | Most recent IF: 3.836; 2009 IF: 3.475 | ||
Call Number | UA @ lucian @ c:irua:78542 | Serial | 1975 | ||
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Author | Fu, Y.; Ding, L.; Singleton, M.L.; Idrissi, H.; Hermans, S. | ||||
Title | Synergistic effects altering reaction pathways : the case of glucose hydrogenation over Fe-Ni catalysts | Type | A1 Journal article | ||
Year | 2021 | Publication | Applied Catalysis B-Environmental | Abbreviated Journal | Appl Catal B-Environ |
Volume | 288 | Issue | Pages | 119997 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Carbon black (CB) supported Ni, Fe, or Fe-Ni alloy catalysts were synthesized by sol-gel to elucidate the reaction pathways over each catalyst, as well as synergistic effects in glucose to sorbitol hydrogenation. The bimetallic materials presented small and alloyed nanoparticles that were richer in reduced metallic sites at the surface than their monometallic counterparts. Glucose isomerization to fructose was favoured over Fe/CB, while glucose hydrogenation to sorbitol is the dominating pathway over Ni/CB catalyst. By contrast, sorbitol production was promoted and undesired isomerization was suppressed when Fe and Ni formed a nanoalloy. In addition, the alloy catalyst presented better stability than the corresponding monometallic catalyst. A comparison with a mechanical mixture of Fe/CB and Ni/CB monometallic catalysts demonstrated the synergy at the nanoscale in the alloy. By comparing different Fe:Ni ratios, the 1:1 formulation was identified as the best compromise to achieve a high activity while maintaining high sorbitol selectivity. | ||||
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Language | Wos | 000632996500002 | Publication Date | 2021-02-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0926-3373 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.446 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 9.446 | |||
Call Number | UA @ admin @ c:irua:177621 | Serial | 6789 | ||
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Author | Coulombier, M.; Baral, P.; Orekhov, A.; Dohmen, R.; Raskin, J.P.; Pardoen, T.; Cordier, P.; Idrissi, H. | ||||
Title | On-chip very low strain rate rheology of amorphous olivine films | Type | A1 Journal article | ||
Year | 2024 | Publication | Acta materialia | Abbreviated Journal | |
Volume | 266 | Issue | Pages | 119693-12 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Recent observations made by the authors revealed the activation of stress induced amorphization and sliding at grain boundary in olivine [1], a mechanism which is expected to play a pivotal role in the viscosity drop at the lithosphere-asthenosphere boundary and the brittle -ductile transition in the lithospheric mantle. However, there is a lack of information in the literature regarding the intrinsic mechanical properties and the elementary deformation mechanisms of this material, especially at time scales relevant for geodynamics. In the present work, amorphous olivine films were obtained by pulsed laser deposition (PLD). The mechanical response including the rate dependent behavior are investigated using a tension -on -chip (TOC) method developed at UCLouvain allowing to perform creep/relaxation tests on thin films at extremely low strain rates. In the present work, strain rate down to 10-12 s- 1 was reached which is unique. High strain rate sensitivity of 0.054 is observed together with the activation of relaxation at the very early stage of deformation. Furthermore, digital image correlation (DIC), used for the first time on films deformed by TOC, reveals local strain heterogeneities. The relationship between such heterogeneities, the high strain rate sensitivity and the effect of the electron beam in the scanning electron microscope is discussed and compared to the literature. | ||||
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Language | Wos | 001170513400001 | Publication Date | 2024-01-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1359-6454 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 9.4 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 9.4; 2024 IF: 5.301 | |||
Call Number | UA @ admin @ c:irua:204864 | Serial | 9163 | ||
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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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Language | Wos | 000861076600004 | Publication Date | 2022-08-05 | |
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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 | Arseenko, M.; Hannard, F.; Ding, L.; Zhao, L.; Maire, E.; Villanova, J.; Idrissi, H.; Simar, A. | ||||
Title | A new healing strategy for metals : programmed damage and repair | Type | A1 Journal article | ||
Year | 2022 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
Volume | 238 | Issue | Pages | 118241-10 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Self-healing strategies aim at avoiding part repair or even replacement, which is time consuming, expen-sive and generates waste. However, strategies for metallic systems are still under-developed and solid-state solutions for room temperature service are limited to nano-scale damage repair. Here we propose a new healing strategy of micron-sized damage requiring only short and low temperature heating. This new strategy is based on damage localization particles, which can be healed by fast diffusing atoms of the matrix activated during heat treatment. The healing concept was successfully validated with a com-mercial aluminum alloy and manufactured by Friction Stir Processing (FSP). Damage was demonstrated to initiate on particles that were added to the matrix during material processing. In situ 2D and 3D nano -imaging confirmed healing of the damaged material and showed that heating this material for 10 min at 400 degrees C is sufficient to heal incipient damage with complete filling of 70% of all damage (and up to 90% when their initial size is below 0.2 mu m). Furthermore, strength is retained and the work of fracture of the alloy is improved by about 40% after healing. The proposed Programmed Damage and Repair healing strategy could be extended to other metal based systems presenting precipitation. (C) 2022 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
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Language | Wos | 000843502700006 | Publication Date | 2022-08-03 | |
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 | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 9.4 | |||
Call Number | UA @ admin @ c:irua:190561 | Serial | 7121 | ||
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Author | Choisez, L.; Ding, L.; Marteleur, M.; Kashiwar, A.; Idrissi, H.; Jacques, P.J. | ||||
Title | Shear banding-activated dynamic recrystallization and phase transformation during quasi-static loading of β-metastable Ti – 12 wt % Mo alloy | Type | A1 Journal article | ||
Year | 2022 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
Volume | 235 | Issue | Pages | 118088-13 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Dynamic recrystallization (DRX) within adiabatic shear bands forming during the fracture of TRIP-TWIP β−metastable Ti-12Mo (wt %) alloy was recently reported. The formation of 1-3 µm thick-adiabatic shear bands, and of dynamic recrystallization, was quite surprising as their occurrence generally requires high temperature and/or high strain rate loading while these samples were loaded in quasi-static conditions at room temperature. To better understand the fracture mechanism and associated microstructural evolution, thin foils representative of different stages of the fracture process were machined from the fracture surface by Focused Ion Beam (FIB) and analyzed by Transmission Electron Microscopy (TEM) and Automated Crystal Orientation mapping (ACOM-TEM). Complex microstructure transformations involving severe plastic deformed nano-structuration, crystalline rotation and local precipitation of the omega phase were identified. The spatial and temporal evolution of the microstructure during the propagation of the crack was explained through dynamic recovery and continuous dynamic recrystallization, and linked to the modelled distribution of temperature and strain level where TEM samples were extracted. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000814729300005 | Publication Date | 2022-06-05 | |
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 | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 9.4 | |||
Call Number | UA @ admin @ c:irua:188505 | Serial | 7096 | ||
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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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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 | Ding, L.; Sapanathan, T.; Schryvers, D.; Simar, A.; Idrissi, H. | ||||
Title | On the formation of antiphase boundaries in Fe₄Al₁₃ intermetallics during a high temperature treatment | Type | A1 Journal article | ||
Year | 2022 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
Volume | 215 | Issue | Pages | 114726-6 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | In this paper, we report atomic scale observations and formation mechanisms of a high-density of antiphase boundaries (APBs) within an ultra-fine-grained Fe4Al13 intermetallic layer at an Al/steel interface after a heat treatment at 596 degrees C. The results reveal that the APBs are formed by nucleation and the glide of partial dislocations with Burgers vector of b/3[010] (b = 12.47 angstrom). The intensive activation of APBs locally transforms the Fe4Al13 structure from the quasicrystal approximant structure to a quasicrystal. Very few stacking faults and nanotwins are observed indicating that the formation of planar defects is mainly driven by this transformation. This new insight on the formation of high density of APBs could possibly lead to an improvement in toughness by increasing the strength/ductility balance of this intermetallic. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000800016600003 | Publication Date | 2022-04-08 | |
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 | 6 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 6 | |||
Call Number | UA @ admin @ c:irua:188644 | Serial | 7088 | ||
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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 | Kashiwar, A.; Arseenko, M.; Simar, A.; Idrissi, H. | ||||
Title | On the role of microstructural defects on precipitation, damage, and healing behavior in a novel Al-0.5Mg2Si alloy | Type | A1 Journal article | ||
Year | 2024 | Publication | Materials & design | Abbreviated Journal | |
Volume | 239 | Issue | Pages | 112765-112769 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | A recently developed healable Al-Mg2Si designed by the programmed damage and repair (PDR) strategy is studied considering the role microstructural defects play on precipitation, damage, and healing. The alloy incorporates sacrificial Mg2Si particles that precipitate after friction stir processing (FSP). They act as damage localization sites and are healable based on the solid-state diffusion of Al-matrix. A combination of different transmission electron microscopy (TEM) imaging techniques enabled the visualization and quantification of various crystallographic defects and the spatial distribution of Mg2Si precipitates. Intragrain nucleation is found to be the dominant mechanism for precipitation during FSP whereas grain boundaries and subgrain boundaries mainly lead to coarsening of the precipitates. The statistical and spatial analyses of the damaged particles have shown particle fracture as the dominant damage mechanism which is strongly dependent on the size and aspect ratio of the particles whereas the damage was not found to depend on the location of the precipitates within the matrix. The damaged particles are associated with dislocations accumulated around them. The interplay of these dislocations is directly visualized during healing based on in situ TEM heating which revealed recovery in the matrix as an operative mechanism during the diffusion healing of the PDR alloy. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001194110200001 | Publication Date | 2024-02-17 | |
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 | |
Impact Factor | 8.4 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 8.4; 2024 IF: 4.364 | |||
Call Number | UA @ admin @ c:irua:203298 | Serial | 9068 | ||
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Author | Gheysen, J.; Kashiwar, A.; Idrissi, H.; Villanova, J.; Simar, A. | ||||
Title | Suppressing hydrogen blistering in a magnesium-rich healable laser powder bed fusion aluminum alloy analyzed by in-situ high resolution techniques | Type | A1 Journal article | ||
Year | 2023 | Publication | Materials & design | Abbreviated Journal | |
Volume | 231 | Issue | Pages | 112024-11 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Hydrogen blistering, i.e. precipitation of supersaturated hydrogen at elevated temperatures, increases porosity during heat treatments in 4xxx series Al alloys manufactured by laser powder bed fusion (LPBF), as demonstrated by 3D X-ray nano-imaging in AlSi12. This paper proposes the design of a healable Al alloy to suppress hydrogen blistering and improve the damage management. The strategy consists of solute atoms diffusing towards nano-voids and precipitating on their surface, thereby filling the damage sites. A new healable Al alloy was thus developed and successfully manufactured by LPBF. 3D X-ray nano-imaging evidenced that the addition of Mg in 4xxx series Al alloys suppresses the hydrogen blistering. This is expectedly due to Mg in solid solution which increases the hydrogen solubility in the Al matrix and due to the healing of these hydrogen pores. Moreover, a significant healing of voids smaller than 500 nm diameter is observed. In-situ heating inside transmission electron microscopy pointed out that Al matrix diffuses inside the fractured Mg2Si particles, thereby demonstrating the healing ability of the new alloy. This has opened the doors to development of new healable Al alloys manufactured by LPBF as well as to new post-treatments to tailor mechanical properties and microstructure without hydrogen blistering. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001055174900001 | Publication Date | 2023-05-20 | |
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; 2023 IF: 4.364 | |||
Call Number | UA @ admin @ c:irua:196536 | Serial | 8939 | ||
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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 | ||||
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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 | ||
Permanent link to this record | |||||
Author | Ding, L.; Raskin, J.-P.; Lumbeeck, G.; Schryvers, D.; Idrissi, H. | ||||
Title | TEM investigation of the role of the polycrystalline-silicon film/substrate interface in high quality radio frequency silicon substrates | Type | A1 Journal article | ||
Year | 2020 | Publication | Materials Characterization | Abbreviated Journal | Mater Charact |
Volume | 161 | Issue | Pages | 110174-10 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The microstructural characteristics of two polycrystalline silicon (poly-Si) films with different electrical properties produced by low-pressure chemical vapour deposition on top of high resistivity silicon substrates were investigated by advanced transmission electron microscopy (TEM), including high resolution aberration corrected TEM and automated crystallographic orientation mapping in TEM. The results reveal that the nature of the poly-Si film/Si substrate interface is the main factor controlling the electrical resistivity of the poly-Si films. The high resistivity and high electrical linearity of poly-Si films are strongly promoted by the Sigma 3 twin type character of the poly-Si/Si substrate interface, leading to the generation of a huge amount of extended defects including stacking faults, Sigma 3 twin boundaries as well as Sigma 9 grain boundaries at this interface. Furthermore, a high density of interfacial dislocations has been observed at numerous common and more exotic grain boundaries deviating from their standard crystallographic planes. In contrast, poly-Si film/Si substrate interfaces with random character do not favour the formation of such complex patterns of defects, leading to poor electrical resistivity of the poly-Si film. This finding opens windows for the development of high resistivity silicon substrates for Radio Frequency (RF) integrated circuits (ICs) applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000521515800027 | Publication Date | 2020-01-30 | |
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 | Not_Open_Access | |
Notes | ; H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). ; | Approved | Most recent IF: 4.7; 2020 IF: 2.714 | ||
Call Number | UA @ admin @ c:irua:168664 | Serial | 6621 | ||
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Author | Zhao, L.; Ding, L.; Soete, J.; Idrissi, H.; Kerckhofs, G.; Simar, A. | ||||
Title | Fostering crack deviation via local internal stresses in Al/NiTi composites and its correlation with fracture toughness | Type | A1 Journal article | ||
Year | 2019 | Publication | Composites: part A: applied science and manufacturing | Abbreviated Journal | Compos Part A-Appl S |
Volume | 126 | Issue | 126 | Pages | 105617 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In the framework of metal matrix composites, a research gap exists regarding tailoring damage mechanisms. The present work aims at developing an Al/NiTi composite incorporating internal stresses in the vicinity of reinforcements. The composite is manufactured by friction stir processing which allows a homogenous NiTi distribution and a good Al/NiTi interface bonding. The internal stresses are introduced via shape memory effect of the embedded NiTi particles. The induced internal strain field is confirmed by digital image correlation and the corresponding stress field is evaluated by finite element simulation. It is found that the damage mechanism is modified in the presence of internal stresses. The consequent enhancement of fracture toughness arises by the fact that the internal stresses foster discrete damages shifted from the fracture ligament line. These damages release the stress concentration at the main crack tip and lead to a deviated crack path when coalescing to accommodate fracture propagation. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000489350600025 | Publication Date | 2019-09-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1359-835x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.075 | Times cited | Open Access | ||
Notes | ; This research work has been exclusively supported by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement no 716678). The X-ray computed,tomography facilities of the Department of Materials Engineering of the KU Leuven are financed by the Hercules Foundation. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). The authors acknowledge Professor F. Delannay from UCLouvain for fruitful discussions. ; | Approved | Most recent IF: 4.075 | ||
Call Number | UA @ admin @ c:irua:163706 | Serial | 5387 | ||
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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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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 | 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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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 | Idrissi, H.; Kobler, A.; Amin-Ahmadi, B.; Coulombier, M.; Galceran, M.; Raskin, J.-P.; Godet, S.; Kuebel, C.; Pardoen, T.; Schryvers, D. | ||||
Title | Plasticity mechanisms in ultrafine grained freestanding aluminum thin films revealed by in-situ transmission electron microscopy nanomechanical testing | Type | A1 Journal article | ||
Year | 2014 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 104 | Issue | 10 | Pages | 101903 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In-situ bright field transmission electron microscopy (TEM) nanomechanical tensile testing and in-situ automated crystallographic orientation mapping in TEM were combined to unravel the elementary mechanisms controlling the plasticity of ultrafine grained Aluminum freestanding thin films. The characterizations demonstrate that deformation proceeds with a transition from grain rotation to intragranular dislocation glide and starvation plasticity mechanism at about 1% deformation. The grain rotation is not affected by the character of the grain boundaries. No grain growth or twinning is detected. (C) 2014 AIP Publishing LLC. | ||||
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Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000333082800022 | Publication Date | 2014-03-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951;1077-3118; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 24 | Open Access | |
Notes | Approved | Most recent IF: 3.411; 2014 IF: 3.302 | |||
Call Number | UA @ lucian @ c:irua:116866 | Serial | 2649 | ||
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Author | Lezaack, M.B.; Hannard, F.; Zhao, L.; Orekhov, A.; Adrien, J.; Miettinen, A.; Idrissi, H.; Simar, A. | ||||
Title | Towards ductilization of high strength 7XXX aluminium alloys via microstructural modifications obtained by friction stir processing and heat treatments | Type | A1 Journal article | ||
Year | 2021 | Publication | Materialia | Abbreviated Journal | |
Volume | 20 | Issue | Pages | 101248 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | High strength 7XXX aluminium series reach exceptional strength, higher than all other industrial aluminium alloys. However, they suffer from a lack of ductility compared to softer series. This work presents a procedure to improve the ductility of 7475 Al alloy in high strength condition, reaching a true fracture strain of 70% at full 500 MPa T6 yield strength. Using friction stir processing (FSP) and post-FSP heat treatments, 100% of industrial rolled material T6 yield stress is maintained but a 180% increase in fracture strain is measured for the processed material. This ductility improvement is studied by in-situ synchrotron X-ray tomography and is explained by the reduction of intermetallic particles size and the homogenization of their spatial distribution. Furthermore, the microstructure after FSP shows equiaxed refined grains which favour crack deviation as opposed to large cracks parallel to the elongated coarse grains in rolled plate. These results are paving the way to better formability and crashworthiness of 7XXX alloys. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000718127100006 | Publication Date | 2021-10-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2589-1529 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | Not_Open_Access | ||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ admin @ c:irua:184145 | Serial | 6894 | ||
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Author | Idrissi, H.; Carrez, P.; Cordier, P. | ||||
Title | On amorphization as a deformation mechanism under high stresses | Type | A1 Journal article | ||
Year | 2022 | Publication | Current opinion in solid state and materials science | Abbreviated Journal | Curr Opin Solid St M |
Volume | 26 | Issue | 1 | Pages | 100976-17 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In this paper we review the work related to amorphization under mechanical stress. Beyond pressure, we highlight the role of deviatoric or shear stresses. We show that the most recent works make amorphization appear as a deformation mechanism in its own right, in particular under extreme conditions (shocks, deformations under high stresses, high strain-rates). | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000779433300002 | Publication Date | 2022-01-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1359-0286 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 11 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 11 | |||
Call Number | UA @ admin @ c:irua:188014 | Serial | 7064 | ||
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Author | Marteleur, M.; Idrissi, H.; Amin-Ahmadi, B.; Prima, F.; Schryvers, D.; Jacques, P.J. | ||||
Title | On the nucleation mechanism of {112} < 111 > mechanical twins in as-quenched beta metastable Ti-12 wt.% Mo alloy | Type | A1 Journal article | ||
Year | 2019 | Publication | Materialia | Abbreviated Journal | |
Volume | 7 | Issue | Pages | Unsp 100418 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Recently developed beta-metastable Ti grades take advantage of the simultaneous activation of TRIP and TWIP effects for enhancing their work hardening rate. However, the role of each plasticity mechanism on the macroscopic mechanical response is still unclear. In this work, the nucleation mechanism of the first activated plasticity mechanism, namely {112} < 111 > twinning, was investigated. Firstly, post-mortem TEM analysis showed that twins nucleate on pre-existing microstructural defects such as thermal jogs with the zonal dislocation mechanism. The precipitation of the omega phase on twin boundaries has been observed, as well as the emission of numerous dislocations from super-jogs present in these twin boundaries. It is also shown that {112} < 111 > twins act as effective dislocation sources for the subsequent plasticity mechanisms such as beta -> alpha '' martensitic transformation and {332} < 111 > twinning. Secondly, in situ TEM tensile testing of the investigated Ti grade highlighted the primary role of the initial defect configuration present in the microstructure. It is shown that twins cannot nucleate without the presence of specific defects allowing the triggering of the dislocation decomposition needed for the twinning mechanism highlighted in investigated bulk samples. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000537131000052 | Publication Date | 2019-07-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2589-1529 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:170326 | Serial | 6875 | ||
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Author | Amin-Ahmadi, B.; Idrissi, H.; Delmelle, R.; Pardoen, T.; Proost, J.; Schryvers, D. | ||||
Title | High resolution transmission electron microscopy characterization of fcc -> 9R transformation in nanocrystalline palladium films due to hydriding | Type | A1 Journal article | ||
Year | 2013 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 102 | Issue | 7 | Pages | 071911-71914 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Sputtered nanocrystalline palladium thin films with nanoscale growth twins have been subjected to hydriding cycles. The evolution of the twin boundaries has been investigated using high resolution transmission electron microscopy. Surprisingly, the Sigma 3{112} incoherent twin boundaries dissociate after hydriding into two phase boundaries bounding a 9R phase. This phase which corresponds to single stacking faults located every three {111} planes in the fcc Pd structure was not expected because of the high stacking fault energy of Pd. This observation is connected to the influence of the Hydrogen on the stacking fault energy of palladium and the high compressive stresses building up during hydriding. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4793512] | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000315596700023 | Publication Date | 2013-02-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 14 | Open Access | |
Notes | Iap | Approved | Most recent IF: 3.411; 2013 IF: 3.515 | ||
Call Number | UA @ lucian @ c:irua:108303 | Serial | 1462 | ||
Permanent link to this record | |||||
Author | Leusink, D.P.; Coneri, F.; Hoek, M.; Turner, S.; Idrissi, H.; Van Tendeloo, G.; Hilgenkamp, H. | ||||
Title | Thin films of the spin ice compound Ho2Ti2O7 | Type | A1 Journal article | ||
Year | 2014 | Publication | APL materials | Abbreviated Journal | Apl Mater |
Volume | 2 | Issue | 3 | Pages | 032101-32107 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The pyrochlore compounds Ho2Ti2O7 and Dy2Ti2O7 show an exotic form of magnetism called the spin ice state, resulting from the interplay between geometrical frustration and ferromagnetic coupling. A fascinating feature of this state is the appearance of magnetic monopoles as emergent excitations above the degenerate ground state. Over the past years, strong effort has been devoted to the investigation of these monopoles and other properties of the spin ice state in bulk crystals. Here, we report the fabrication of Ho2Ti2O7 thin films using pulsed laser deposition on yttria-stabilized ZrO2 substrates. We investigated the structural properties of these films by X-ray diffraction, scanning transmission electron microscopy, and atomic force microscopy, and the magnetic properties by vibrating sample magnetometry at 2 K. The films not only show a high crystalline quality, but also exhibit the hallmarks of a spin ice: a pronounced magnetic anisotropy and an intermediate plateau in the magnetization along the [111] crystal direction. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000334220300002 | Publication Date | 2014-03-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2166-532X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.335 | Times cited | 18 | Open Access | |
Notes | The authors acknowledge support from the Dutch FOM and NWO foundations and from the European Union under the Framework 7 program under a contract from an Integrated Infrastructure Initiative (Reference 312483 ESTEEM2). G.V.T. acknowledges the ERC Grant N246791- COUNTATOMS. S.T. gratefully acknowledges financial support from the Fund for Scientific Research Flanders (FWO). H.I. acknowledges the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs under Contract No. P7/21. The microscope used in this study was partially financed by the Hercules Foundation of the Flemish Government. The authors acknowledge fruitful interactions with A. Brinkman, M. G. Blamire, M. Egilmez, F. J. G. Roesthuis, J. N. Beukers, C. G. Molenaar, M. Veldhorst, and X. Renshaw Wang; esteem2_ta | Approved | Most recent IF: 4.335; 2014 IF: NA | ||
Call Number | UA @ lucian @ c:irua:115555 | Serial | 3641 | ||
Permanent link to this record |