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| Author | Viart, N.; Sayed Hassan, R.; Ulhaq-Bouillet, C.; Meny, C.; Panissod, P.; Loison, J.L.; Versini, G.; Huber, F.; Pourroy, G.; Verbeeck, J.; Van Tendeloo, G. | ||||
| Title | Oxidation processes at the metal/oxide interface in CoFe2/CoFe2O4 bilayers deposited by pulsed laser deposition | Type | A1 Journal article | ||
| Year | 2006 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 54 | Issue  |
1 | Pages | 191-196 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | CoFe2/CoFe2O4 bilayers were made by pulsed laser ablation of a CoFe2 target on Si(I 0 0) substrates. The metallic layer was deposited first, in vacuum. The oxide was then deposited in an oxidizing O-2:N-2 (20:80) atmosphere. Two different procedures were used for the introduction of the oxidizing atmosphere in the deposition chamber: the laser ablation of the target was either stopped (discontinuous deposition process) or maintained (continuous deposition process) during the 20 min necessary for the establishment of the desired O-2:N-2 pressure. In both cases, the different electronegativities of Fe and Co cause an important modification of the Fe/Co ratio at the metal/oxide interface, with a depletion of Fe in the metal region and of Co in the oxide region. In the continuous procedure, the combination of the kinetic energy given by the ablation process to the Fe and Co adatoms with the one they get from their different affinity towards oxidation allows the formation of a low roughness metal/oxide interface with a high (111) preferred orientation of the CoFe2O4 layer, an induced re-crystallisation of the metal layer underneath and an unusual antiferromagnetic metal/oxide magnetic coupling. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000233784500021 | Publication Date | 2005-10-15 | |
| 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 | |
| Notes | Approved | Most recent IF: 5.301; 2006 IF: 3.549 | |||
| Call Number | UA @ lucian @ c:irua:56043UA @ admin @ c:irua:56043 | Serial | 2540 | ||
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| Author | Idrissi, H.; Renard, K.; Schryvers, D.; Jacques, P.J. | ||||
| Title | On the relationship between the twin internal structure and the work-hardening rate of TWIP steels | Type | A1 Journal article | ||
| Year | 2010 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
| Volume | 63 | Issue |
10 | Pages | 961-964 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | FeMnC and FeMnSiAl TWIP steels deformed under the same conditions exhibit different work-hardening rates. The present study investigates the microstructure of plastically deformed FeMnC and FeMnSiAl samples, particularly the internal structure of the mechanically generated twins and their topology at the grain scale. Twins in the FeMnC steel are finer and full of sessile dislocations, rendering this material distinctly stronger with an improved work-hardening rate. | ||||
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| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000282461800003 | Publication Date | 2010-07-20 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6462; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.747 | Times cited | 145 | Open Access | |
| Notes | Iap | Approved | Most recent IF: 3.747; 2010 IF: 2.820 | ||
| Call Number | UA @ lucian @ c:irua:84472 | Serial | 2452 | ||
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| Author | Pollefeyt, G.; Meledin, A.; Pop, C.; Ricart, S.; Hühne, R.; Van Tendeloo, G.; Van Driessche, I. | ||||
| Title | Chemical stability of YBiO3 buffer layers for implementation in YBa2Cu3O7-δ coated conductors | Type | A1 Journal article | ||
| Year | 2015 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 100 | Issue |
100 | Pages | 224-231 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In this work, the chemical and microstructural stability of YBiO3 buffer layers during the growth of YBa2Cu3O7-δ (YBCO) was studied. The superconducting YBCO films were deposited via both Pulsed Laser Deposition as well as Chemical Solution Deposition. Although excellent superconducting properties are obtained in both cases, self-field critical current densities of 3.6 and 1.2 MA/cm2 respectively, chemical instability of the YBiO3 buffer layer is observed. An elaborate transmission electron microscopy study showed that in the case of vacuum deposited YBCO, the YBiO3 becomes unstable and Bi2O3 sublimates out of the architecture. Due to this structural instability, an intermediate Y2O3 layer is obtained which maintains it microstructural orientation relation with the substrate and acts as growth template for YBCO. For chemical solution deposited YBCO, reaction of YBCO with the YBiO3 buffer layer is observed, leading to large grains of YBa2BiO6 which are pushed towards the surface of the films and strongly reduce the superconducting properties. Upon using high growth temperatures for the superconducting layer, these secondary phases decompose, which subsequently leads to Bi2O3 sublimation and a textured YBCO film which directly nucleated onto the LaAlO3 single crystal substrate. Hence, this electron microscopy study indicates that bismuth-based buffer layers systems are not suitable for implementation in coated conductors. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000362616400023 | Publication Date | 2015-08-29 | |
| 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 | 5.301 | Times cited | Open Access | ||
| Notes | One of the authors (G.P.) would like to thank the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT) for funding. Part of this work was performed within the framework of the EuroTapes project (FP7-NMP.2011.2.2-1 Grant No. 280438), funded by the European Union. | Approved | Most recent IF: 5.301; 2015 IF: 4.465 | ||
| Call Number | c:irua:128757 | Serial | 3953 | ||
| Permanent link to this record | |||||
| Author | Zhang, F.; Batuk, M.; Hadermann, J.; Manfredi, G.; Mariën, A.; Vanmeensel, K.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J. | ||||
| Title | Effect of cation dopant radius on the hydrothermal stability of tetragonal zirconia: Grain boundary segregation and oxygen vacancy annihilation | Type | A1 Journal article | ||
| Year | 2016 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 106 | Issue |
106 | Pages | 48-58 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The hydrothermal aging stability of 3Y-TZP-xM2O3 (M = La, Nd, Sc) was investigated as a function of 0.02–5 mol% M2O3 dopant content and correlated to the overall phase content, t-ZrO2 lattice parameters, grain size distribution, grain boundary chemistry and ionic conductivity. The increased aging stability with increasing Sc2O3 content and the optimum content of 0.4–0.6 mol% Nd2O3 or 0.2–0.4 mol% La2O3, resulting in the highest aging resistance, could be directly related to the constituent phases and the lattice parameters of the remaining tetragonal zirconia. At low M2O3 dopant contents ≤0.4 mol%, the different aging behavior of tetragonal zirconia was attributed to the defect structure of the zirconia grain boundary which was influenced by the dopant cation radius. It was observed that the grain boundary ionic resistivity and the aging resistance followed the same trend: La3+ > Nd3+ > Al3+ > Sc3+, proving that hydrothermal aging is driven by the diffusion of water-derived mobile species through the oxygen vacancies. Accordingly, we elucidated the underlying mechanism by which a larger trivalent cation segregating at the zirconia grain boundary resulted in a higher aging resistance. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000371650300006 | Publication Date | 2016-01-08 | |
| 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 | 37 | Open Access | |
| Notes | The authors acknowledge the Research Fund of KU Leuven under project 0T/10/052 and the Fund for Scientific Research Flanders (FWO-Vlaanderen) under grant G.0431.10N. F. Zhang thanks the Research Fund of KU Leuven for her post-doctoral fellowship (PDM/15/153). | Approved | Most recent IF: 5.301 | ||
| Call Number | c:irua:132435 | Serial | 4076 | ||
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| Author | Yang, Z.; Tirry, W.; Schryvers, D. | ||||
| Title | Analytical TEM investigations on concentration gradients surrounding Ni4Ti3 precipitates in Ni-Ti shape memory material | Type | A1 Journal article | ||
| Year | 2005 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
| Volume | 52 | Issue |
11 | Pages | 1129-1134 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000228190200010 | Publication Date | 2005-03-16 | |
| 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 | 49 | Open Access | |
| Notes | GOA project; MCRTN-FP6-505226 Multimat | Approved | Most recent IF: 3.747; 2005 IF: 2.228 | ||
| Call Number | UA @ lucian @ c:irua:55687 | Serial | 110 | ||
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| Author | Schryvers, D.; Ma, Y.; Toth, L.; Tanner, L.E. | ||||
| Title | Electron microscopy study of the formation of Ni5Al3 in a Ni62.5Al37.5 B2 alloy: 1: precipitation and growth | Type | A1 Journal article | ||
| Year | 1995 | Publication | Acta metallurgica et materialia | Abbreviated Journal | |
| Volume | 43 | Issue |
11 | Pages | 4045-4056 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York | Editor | ||
| Language | Wos | A1995TA33200014 | Publication Date | 2003-12-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0956-7151; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 27 | Open Access | ||
| Notes | Approved | no | |||
| Call Number | UA @ lucian @ c:irua:13164 | Serial | 973 | ||
| Permanent link to this record | |||||
| Author | Schryvers, D.; Ma, Y.; Toth, L.; Tanner, L.E. | ||||
| Title | Electron microscopy study of the formation of Ni5Al3 in a Ni62.5Al37.5 B2 alloy: 2: plate crystallography | Type | A1 Journal article | ||
| Year | 1995 | Publication | Acta metallurgica et materialia | Abbreviated Journal | |
| Volume | 43 | Issue |
11 | Pages | 4057-4065 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York | Editor | ||
| Language | Wos | A1995TA33200015 | Publication Date | 2003-12-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0956-7151; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 11 | Open Access | ||
| Notes | Approved | no | |||
| Call Number | UA @ lucian @ c:irua:13165 | Serial | 974 | ||
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| Author | Idrissi, H.; Ryelandt, L.; Veron, M.; Schryvers, D.; Jacques, P.J. | ||||
| Title | Is there a relationship between the stacking fault character and the activated mode of plasticity of FeMn-based austenitic steels? | Type | A1 Journal article | ||
| Year | 2009 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
| Volume | 60 | Issue |
11 | Pages | 941-944 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | By changing the testing temperature, an austenitic FeMnAlSi alloy presents either å-martensite transformation or mechanical twinning during straining. In order to understand the nucleation and growth mechanisms involved in both phenomena, defects and particularly stacking faults, were characterized by transmission electron microscopy. It is observed that the character of the stacking faults also changes (from extrinsic to intrinsic) together with the temperature and the activated mode of plasticity. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000265359900005 | Publication Date | 2009-02-10 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6462; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.747 | Times cited | 84 | Open Access | |
| Notes | Iap | Approved | Most recent IF: 3.747; 2009 IF: 2.949 | ||
| Call Number | UA @ lucian @ c:irua:77276 | Serial | 1751 | ||
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| Author | Wang, B.; Idrissi, H.; Shi, H.; Colla, M.S.; Michotte, S.; Raskin, J.P.; Pardoen, T.; Schryvers, D. | ||||
| Title | Texture-dependent twin formation in nanocrystalline thin Pd films | Type | A1 Journal article | ||
| Year | 2012 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
| Volume | 66 | Issue |
11 | Pages | 866-871 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Nanocrystalline Pd films were produced by electron-beam evaporation and sputter deposition. The electron-beam-evaporated films reveal randomly oriented nanograins with a relatively high density of growth twins, unexpected in view of the high stacking fault energy of Pd. In contrast, sputter-deposited films show a clear 〈1 1 1〉 crystallographic textured nanostructure without twins. These results provide insightful information to guide the generation of microstructures with enhanced strength/ductility balance in high stacking fault energy nanocrystalline metallic thin films. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000303621900007 | Publication Date | 2012-01-31 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6462; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.747 | Times cited | 19 | Open Access | |
| Notes | Iap; Fwo | Approved | Most recent IF: 3.747; 2012 IF: 2.821 | ||
| Call Number | UA @ lucian @ c:irua:96955 | Serial | 3566 | ||
| 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. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000375812100027 | Publication Date | 2016-04-06 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6454 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 5.301 | Times cited | 14 | Open Access | |
| Notes | This work was carried out in the framework of the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs, under Contract No. P7/21. The support of the FWO research project G012012N “Understanding nanocrystalline mechanical behaviour from structural investigations” for B. Amin-Ahmadi is also gratefully acknowledged. This work was granted access to the HPC resources of CALMIP (CICT Toulouse, France) under the allocations 2014-p0912 and 2014-p0749. | Approved | Most recent IF: 5.301 | ||
| Call Number | c:irua:132678 | Serial | 4054 | ||
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| Author | 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. | ||||
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| 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 | Shi, H.; Pourbabak, S.; Van Humbeeck, J.; Schryvers, D. | ||||
| Title | Electron microscopy study of Nb-rich nanoprecipitates in NiTiNb and their influence on the martensitic transformation | Type | A1 Journal article | ||
| Year | 2012 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
| Volume | 67 | Issue |
12 | Pages | 939-942 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Nb-rich nanoprecipitates in the matrix of an annealed commercial NiTiNb alloy are investigated by scanning and transmission electron microscopy, including slice-and-view and chemical analysis. The precipitates have a diameter of around 100 nm, are faceted and have a cube-on-cube relation with the B2 matrix. In situ TEM cooling shows that the martensitic transformation is hampered by the presence of these precipitates. The latter could explain the increase in hysteresis when compared with the binary system. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000311135000005 | Publication Date | 2012-08-27 | |
| 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 | 29 | Open Access | |
| Notes | Fwo | Approved | Most recent IF: 3.747; 2012 IF: 2.821 | ||
| Call Number | UA @ lucian @ c:irua:101486 | Serial | 971 | ||
| Permanent link to this record | |||||
| Author | Renard, K.; Idrissi, H.; Schryvers, D.; Jacques, P.J. | ||||
| Title | On the stress state dependence of the twinning rate and work hardening in twinning-induced plasticity steels | Type | A1 Journal article | ||
| Year | 2012 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
| Volume | 66 | Issue |
12 | Pages | 966-971 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The influence of the stress state on the twinning rate and work hardening is studied in the case of an FeMnC TWIP steel strained in uniaxial tension, simple shear and rolling. The resulting stressstrain responses exhibit marked differences. The twinning rate, number of activated twinning systems in each grain, twin thickness and transmission of twins across grain boundaries are dependent on the imposed stress state during straining. Relationships between twin features and macroscopic work hardening rate are established. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000304641500004 | Publication Date | 2012-02-10 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6462; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.747 | Times cited | 41 | Open Access | |
| Notes | Iap | Approved | Most recent IF: 3.747; 2012 IF: 2.821 | ||
| Call Number | UA @ lucian @ c:irua:98374 | Serial | 2454 | ||
| Permanent link to this record | |||||
| 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. | ||||
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| Language | Wos | 000394201500003 | Publication Date | 2016-12-02 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6454 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 5.301 | Times cited | 5 | Open Access | OpenAccess |
| Notes | This work has been funded by the Belgian Science Policy through the IAP 7/21 project. The support of the ‘Fonds Belge pour la Recherche dans l’Industrie et l’Agriculture (FRIA)’ for A.v.d.R. is also gratefully acknowledged, as well as the support of FNRS through the grant PDR T.0122.13 “Mecano”. | Approved | Most recent IF: 5.301 | ||
| Call Number | EMAT @ emat @ c:irua:138990 | Serial | 4330 | ||
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| Author | Rotaru, G.-M.; Tirry, W.; Sittner, P.; van Humbeeck, J.; Schryvers, D. | ||||
| Title | Microstructural study of equiatomic PtTi martensite and the discovery of a new long-period structure | Type | A1 Journal article | ||
| Year | 2007 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 55 | Issue |
13 | Pages | 4447-4454 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000248436400021 | Publication Date | 2007-06-04 | |
| 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 | 7 | Open Access | |
| Notes | Fwo G.0465.05; Multimat | Approved | Most recent IF: 5.301; 2007 IF: 3.624 | ||
| Call Number | UA @ lucian @ c:irua:65849 | Serial | 2047 | ||
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| Author | Delville, R.; Malard, B.; Pilch, J.; Schryvers, D. | ||||
| Title | Microstructure changes during non-conventional heat treatment of thin NiTi wires by pulsed electric current studied by transmission electron microscopy | Type | A1 Journal article | ||
| Year | 2010 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 58 | Issue |
13 | Pages | 4503-4515 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Transmission electron microscopy, electrical resistivity measurements and mechanical testing were employed to investigate the evolution of microstructure and functional superelastic properties of 0.1 mm diameter as-drawn NiTi wires subjected to a non-conventional heat treatment by controlled electric pulse currents. This method enables a better control of the recovery and recrystallization processes taking place during the heat treatment and accordingly a better control on the final microstructure. Using a stepwise approach of millisecond pulse annealing, it is shown how the microstructure evolves from a severely deformed state with no functional properties to an optimal nanograined microstructure (2050 nm) that is partially recovered through polygonization and partially recrystallized and that has the best functional properties. Such a microstructure is highly resistant against dislocation slip upon cycling, while microstructures annealed for longer times and showing mostly recrystallized grains were prone to dislocation slip, particularly as the grain size exceeds 200 nm. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000279787100020 | Publication Date | 2010-06-02 | |
| 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 | 110 | Open Access | |
| Notes | Multimat; FWO IAA | Approved | Most recent IF: 5.301; 2010 IF: 3.791 | ||
| Call Number | UA @ lucian @ c:irua:83279 | Serial | 2062 | ||
| Permanent link to this record | |||||
| 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 | ||
| Permanent link to this record | |||||
| Author | Chen, X.; Cao, S.; Ikeda, T.; Srivastava, V.; Snyder, G.J.; Schryvers, D.; James, R.D. | ||||
| Title | A weak compatibility condition for precipitation with application to the microstructure of PbTe-Sb2Te3 thermoelectrics | Type | A1 Journal article | ||
| Year | 2011 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 59 | Issue |
15 | Pages | 6124-6132 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We propose a weak condition of compatibility between phases applicable to cases exhibiting full or partial coherence and Widmanstätten microstructure. The condition is applied to the study of Sb2Te3 precipitates in a PbTe matrix in a thermoelectric alloy. The weak condition of compatibility predicts elongated precipitates lying on a cone determined by a transformation stretch tensor. Comparison of this cone with the long directions of precipitates determined by a slice-and-view method of scanning electron microscopy combined with focused ion beam sectioning shows good agreement between theory and experiment. A further study of the morphology of precipitates by the Eshelby method suggests that interfacial energy also plays a role and gives an approximate value of interfacial energy per unit area of 250 dyn cm−1. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000294086900026 | Publication Date | 2011-07-22 | |
| 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 | 8 | Open Access | |
| Notes | Approved | Most recent IF: 5.301; 2011 IF: 3.755 | |||
| Call Number | UA @ lucian @ c:irua:92388 | Serial | 3911 | ||
| Permanent link to this record | |||||
| Author | Zhang, F.; Vanmeensel, K.; Batuk, M.; Hadermann, J.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J. | ||||
| Title | Highly-translucent, strong and aging-resistant 3Y-TZP ceramics for dental restoration by grain boundary segregation | Type | A1 Journal article | ||
| Year | 2015 | Publication | Acta biomaterialia | Abbreviated Journal | Acta Biomater |
| Volume | 16 | Issue |
16 | Pages | 215-222 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Latest trends in dental restorative ceramics involve the development of full-contour 3Y-TZP ceramics which can avoid chipping of veneering porcelains. Among the challenges are the low translucency and the hydrothermal stability of 3Y-TZP ceramics. In this work, different trivalent oxides (Al2O3, Sc2O3, Nd2O3 and La2O3) were selected to dope 3Y-TZP ceramics. Results show that dopant segregation was a key factor to design hydrothermally stable and high-translucent 3Y-TZP ceramics and the cation dopant radius could be used as a controlling parameter. A large trivalent dopant, oversized as compared to Zr4+, exhibiting strong segregation at the ZrO2 grain boundary was preferred. The introduction of 0.2 mol% La2O3 in conventional 0.10.25 wt.% Al2O3-doped 3Y-TZP resulted in an excellent combination of high translucency and superior hydrothermal stability, while retaining excellent mechanical properties. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | S.l. | Editor | ||
| Language | Wos | 000351978600021 | Publication Date | 2015-02-04 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1742-7061; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 6.319 | Times cited | 54 | Open Access | |
| Notes | Fwo G043110n | Approved | Most recent IF: 6.319; 2015 IF: 6.025 | ||
| Call Number | c:irua:124421 | Serial | 1473 | ||
| Permanent link to this record | |||||
| Author | Bartova, B.; Wiese, N.; Schryvers, D.; Chapman, J.N.; Ignacova, S. | ||||
| Title | Microstructure of precipitates and magnetic domain structure in an annealed Co38Ni33Al29 shape memory alloy | Type | A1 Journal article | ||
| Year | 2008 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 56 | Issue |
16 | Pages | 4470-4476 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The microstructure of a Co38Ni33Al29 ferromagnetic shape memory alloy was determined by conventional transmission electron microscopy (TEM), electron diffraction studies together with advanced microscopy techniques and in situ Lorentz microscopy. Rod-like precipitates, 1060 nm long, of hexagonal close-packed -Co were confirmed to be present by high-resolution TEM. The orientation relationship between the precipitates and B2 matrix is described by the Burgers orientation relationship. The crystal structure of the martensite obtained after cooling is tetragonal L10 with a (111) twinning plane. The magnetic domain structure was determined during an in situ cooling experiment using the Fresnel mode of Lorentz microscopy. While transformation proceeds from B2 austenite to L10 martensite, new domains are nucleated, leading to a decrease in domain width, with the magnetization lying predominantly along a single direction. It was possible to completely describe the relationship between magnetic domains and crystallographic directions in the austenite phase though complications existed for the martensite phase. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000259931300033 | Publication Date | 2008-06-11 | |
| 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 | 23 | Open Access | |
| Notes | Multimat | Approved | Most recent IF: 5.301; 2008 IF: 3.729 | ||
| Call Number | UA @ lucian @ c:irua:72321 | Serial | 2072 | ||
| Permanent link to this record | |||||
| Author | Charalampopoulou, E.; Cautaerts, N.; Van der Donck, T.; Schryvers, D.; Lambrinou, K.; Delville, R. | ||||
| Title | Orientation relationship of the austenite-to-ferrite transformation in austenitic stainless steels due to dissolution corrosion in contact with liquid Pb-Bi eutectic | Type | A1 Journal article | ||
| Year | 2019 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
| Volume | 167 | Issue |
167 | Pages | 66-70 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The orientation relationship of an austenite-to-ferrite phase transformation in 316L stainless steels induced by the loss of austenite stabilizers resulting from the steel dissolution corrosion in liquid Pb-Bi eutectic was studied by means of electron backscatter diffraction. The misorientations at the austenite/ferrite interface were compared to the prevailing orientation relationship models in steels. The Pitsch orientation relationship model was found to be predominant, which is unusual for austenite-to-ferrite bulk transformations in steels. The nature of this particular transformation, which involves loss of steel alloying elements and the presence of an interfacial liquid metal layer, is discussed to explain this finding. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000468720000014 | Publication Date | 2019-04-06 | |
| 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 | 3 | Open Access | Not_Open_Access |
| Notes | ; The authors would like to thank J. Joris (SCK center dot CEN) for technical support during corrosion testing, J. Lim (SCK center dot CEN) for the manufacture and calibration of the oxygen sensors used in this work and W. Van Renterghem (SCK center dot CEN) for his valuable help with the EBSD measurements. The steel suppliers were: Industeel, ArcelorMittal Group, for the 316L-SA plate, and Panchmahal Steel Ltd., India, for the 316L-CWrod. The authors gratefully acknowledge the financial support provided within the framework of the ongoing development of the MYRRHA irradiation facility. The research leading to these results falls within the framework of the European Energy Research Alliance Joint Programme on Nuclear Materials (EERA JPNM). ; | Approved | Most recent IF: 3.747 | ||
| Call Number | UA @ admin @ c:irua:160228 | Serial | 5257 | ||
| Permanent link to this record | |||||
| Author | Zhang, Z.; Rosalie, J.M.; Medhekar, N.V.; Bourgeois, L. | ||||
| Title | Resolving the FCC/HCP interfaces of the \gamma'(Ag2Al) precipitate phase in aluminium | Type | A1 Journal article | ||
| Year | 2019 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 174 | Issue |
174 | Pages | 116-130 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The gamma'(Ag2Al) phase in the Al-Ag alloy system has served as a textbook example for understanding phase transformations, precipitating hexagonal close-packed (HCP) crystals in the face-centred cubic (FCC) aluminium matrix. The gamma' precipitates display fully coherent interfaces at their broad facets and semicoherent interfaces at their edges. Shockley partial dislocations are expected to decorate the semicoherent interface due to the FCC-HCP structural transformation. Determining the exact locations and core structures of interfacial dislocations, however, remains challenging. In this study, we used aberration-corrected scanning transmission electron microscopy and atomistic simulations to re-visit this classical system. We characterised and explained the Ag segregation at coherent interfaces in the early stage of precipitation. For semicoherent interfaces, interfacial dislocations and reconstructions were revealed by bridging advanced microstructure characterisation and atomistic simulations. In particular, we discovered a new FCC/HCP interfacial structure that displays a unique combination of Shockley partial, Lomer-Cottrell and Hirth dislocations that evolve from the known interfacial structure purely composed by Shockley partial dislocations. Our findings show that the FCC-HCP transformation is more complex than hitherto considered, due to the interplay between structure and composition confined at interfaces. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000474501300011 | Publication Date | 2019-05-18 | |
| 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 | 3 | Open Access | |
| Notes | ; The authors acknowledge funding from the Australian Research Council (LE0454166, LE110100223), the Victorian State Government and Monash University for instrumentation, and use of the facilities within the Monash Centre for Electron Microscopy. LB and NM acknowledge the financial support of the Australian Research Council (DP150100558). The authors also gratefully acknowledge the computational support from Monash Advanced Research Computing Hybrid, the National Computational Infrastructure and Pawsey Supercomputing Centre. ZZ is thankful to Monash University for a Monash Graduate Scholarship, a Monash International Postgraduate Research Scholarship and a Monash Centre for Electron Microscopy Postgraduate Scholarship. ZZ is indebted to Matthew Weyland for his training in aberration-corrected electron microscopy, Scott Findlay for his help on image simulations, Xiang Gao for alloy casting and Ian Polmear for discussions. ; | Approved | Most recent IF: 5.301 | ||
| Call Number | UA @ admin @ c:irua:161192 | Serial | 5395 | ||
| Permanent link to this record | |||||
| Author | Weng, Y.; Ding, L.; Zhang, Z.; Jia, Z.; Wen, B.; Liu, Y.; Muraishi, S.; Li, Y.; Liu, Q. | ||||
| Title | Effect of Ag addition on the precipitation evolution and interfacial segregation for Al-Mg-Si alloy | Type | A1 Journal article | ||
| Year | 2019 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 180 | Issue |
180 | Pages | 301-316 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The effect of Ag addition on the precipitation evolution and interfacial segregation for Al-Mg-Si alloys was systematically investigated by atomic resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), atom probe tomography (APT) and density functional theory (DFT) calculation. At the early aging stage, Ag atoms could enter clusters and refine the distribution of these clusters. Then, Ag atoms preferentially segregate at the GP zone/alpha-Al and beta ''/alpha-Al interfaces at the peak aging stage by the replacement of Al atoms in FCC matrix. With prolonging aging time, Ag atoms generally incorporate into the interior of beta '' precipitate, facilitating the formation of QP lattice (a hexagonal network of Si atomic columns) and the local symmetry substructures, Ag sub-unit (1) and Ag sub-unit (2). At the over-aged stage, the Ag sub-unit (1) and Ag sub-unit (2) could transform to the beta'(Ag) (i.e. beta'(Ag1) and beta'(Ag2).) and Q'(Ag) unit cells, respectively. All the precipitates at the over-aging stage have a composite and disordered structure due to the coexistence of different unit cells (beta'(Ag1), beta'(Ag2), Q'(Ag) and beta') and the non-periodic arrangement of Ag atoms within the precipitate. In the equilibrium stage, the incorporated Ag atoms in the precipitates release into the alpha-Al matrix as solute atoms or form Ag particles. In general, Ag atoms undergo a process of “segregate at the precipitate/matrix interface -> incorporate into the interior of precipitate -> release into the alpha-Al matrix” during the precipitation for Al-Mg-Si-Ag alloys. Besides, Ag segregation is found at the interfaces of almost all metastable phases (including GP zone, beta '', beta'/beta'(Ag) phase) in Al-Mg-Si-Ag alloys. The Ag segregation at the beta'/alpha-Al interface could increase the length/diameter ratio of beta' phase and thus promote the additional strengthening potential of these alloys. These findings provide a new route for precipitation hardening by promoting the nucleation and morphology evolution of precipitates. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000495519100028 | Publication Date | 2019-09-12 | |
| 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 | Open Access | ||
| Notes | Approved | Most recent IF: 5.301 | |||
| Call Number | UA @ admin @ c:irua:164641 | Serial | 6295 | ||
| Permanent link to this record | |||||
| Author | Tirumalasetty, G.K.; van Huis, M.A.; Fang, C.M.; Xu, Q.; Tichelaar, F.D.; Hanlon, D.N.; Sietsma, J.; Zandbergen, H.W. | ||||
| Title | Characterization of NbC and (Nb, Ti)N nanoprecipitates in TRIP assisted multiphase steels | Type | A1 Journal article | ||
| Year | 2011 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 59 | Issue |
19 | Pages | 7406-7415 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Multiphase steels utilising composite strengthening may be further strengthened via grain refinement or precipitation by the addition of microalloying elements. In this study a Nb microalloyed steel comprising martensite, bainite and retained austenite has been studied. By means of transmission electron microscopy (TEM) we have investigated the size distribution and the structural properties of (Nb, Ti)N and NbC precipitates, their occurrence in the various steel phases, and their relationship with the Fe matrix. (Nb, Ti)N precipitates were found in ferrite, martensite, and bainite, while NbC precipitates were found only in ferrite. All NbC precipitates were found to be small (520 nm in size) and to have a face centred cubic (fcc) crystal structure with lattice parameter a = 4.36 ± 0.05 Å. In contrast, the (Nb, Ti)N precipitates were found to have a broader size range (5150 nm) and to have a fcc crystal structure with lattice parameter a = 8.09 ± 0.05 Å. While the NbC precipitates were found to be randomly oriented, the (Nb, Ti)N precipitates have a well-defined NishiyamaWasserman orientation relationship with the ferrite matrix. An analysis of the lattice mismatch suggests that the latter precipitates have a high potential for effective strengthening. Density functional theory calculations were performed for various stoichiometries of NbCx and NbxTiyNz phases and the comparison with experimental data indicates that both the carbides and nitrides are deficient in C and N content. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000296405200026 | Publication Date | 2011-09-29 | |
| 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 | 58 | Open Access | |
| Notes | Approved | Most recent IF: 5.301; 2011 IF: 3.755 | |||
| Call Number | UA @ lucian @ c:irua:93297 | Serial | 328 | ||
| Permanent link to this record | |||||
| Author | Tian, H.; Schryvers, D.; Liu, D.; Jiang, Q.; van Humbeeck, J. | ||||
| Title | Stability of Ni in nitinol oxide surfaces | Type | A1 Journal article | ||
| Year | 2011 | Publication | Acta biomaterialia | Abbreviated Journal | Acta Biomater |
| Volume | 7 | Issue |
2 | Pages | 892-899 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The stability of Ni in titanium oxide surface layers on nitinol wires known to release certain amounts of Ni was investigated by first principles density functional theory and transmission electron microscopy. The oxides were identified as a combination of TiO and TiO2 depending on the thickness of the layer. The calculations indicate that free Ni atoms can exist in TiO at ambient temperature while Ni particles form in TiO2, which was confirmed by the transmission electron microscopy observations. The results are discussed with respect to surface stability and Ni release due to free Ni atoms and Ni particles. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | S.l. | Editor | ||
| Language | Wos | 000286707700047 | Publication Date | 2010-09-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1742-7061; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 6.319 | Times cited | 39 | Open Access | |
| Notes | Fwo | Approved | Most recent IF: 6.319; 2011 IF: 4.865 | ||
| Call Number | UA @ lucian @ c:irua:85998 | Serial | 3128 | ||
| Permanent link to this record | |||||
| Author | Tirumalasetty, G.K.; van Huis, M.A.; Kwakernaak, C.; Sietsma, J.; Sloof, W.G.; Zandbergen, H.W. | ||||
| Title | Deformation-induced austenite grain rotation and transformation in TRIP-assisted steel | Type | A1 Journal article | ||
| Year | 2012 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 60 | Issue |
3 | Pages | 1311-1321 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Uniaxial straining experiments were performed on a rolled and annealed Si-alloyed TRIP (transformation-induced plasticity) steel sheet in order to assess the role of its microstructure on the mechanical stability of austenite grains with respect to martensitic transformation. The transformation behavior of individual metastable austenite grains was studied both at the surface and inside the bulk of the material using electron back-scattered diffraction (EBSD) and X-ray diffraction (XRD) by deforming the samples to different strain levels up to about 20%. A comparison of the XRD and EBSD results revealed that the retained austenite grains at the surface have a stronger tendency to transform than the austenite grains in the bulk of the material. The deformation-induced changes of individual austenite grains before and after straining were monitored with EBSD. Three different types of austenite grains can be distinguished that have different transformation behaviors: austenite grains at the grain boundaries between ferrite grains, twinned austenite grains, and embedded austenite grains that are completely surrounded by a single ferrite grain. It was found that twinned austenite grains and the austenite grains present at the grain boundaries between larger ferrite grains typically transform first, i.e. are less stable, in contrast to austenite grains that are completely embedded in a larger ferrite grain. In the latter case, straining leads to rotations of the harder austenite grain within the softer ferrite matrix before the austenite transforms into martensite. The analysis suggests that austenite grain rotation behavior is also a significant factor contributing to enhancement of the ductility. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000301157900054 | Publication Date | 2011-12-19 | |
| 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 | 80 | Open Access | |
| Notes | Approved | Most recent IF: 5.301; 2012 IF: 3.941 | |||
| Call Number | UA @ lucian @ c:irua:97210 | Serial | 630 | ||
| Permanent link to this record | |||||
| Author | Yang, Z.; Tirry, W.; Lamoen, D.; Kulkova, S.; Schryvers, D. | ||||
| Title | Electron energy-loss spectroscopy and first-principles calculation studies on a Ni-Ti shape memory alloy | Type | A1 Journal article | ||
| Year | 2008 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 56 | Issue |
3 | Pages | 395-404 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000253020900011 | Publication Date | 2007-12-01 | |
| 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 | 20 | Open Access | |
| Notes | Goa; Ec Rtn; Fwo | Approved | Most recent IF: 5.301; 2008 IF: 3.729 | ||
| Call Number | UA @ lucian @ c:irua:67462 | Serial | 931 | ||
| Permanent link to this record | |||||
| Author | Fang, C.M.; van Huis, M.A.; Zandbergen, H.W. | ||||
| Title | Stability and structures of the \epsilon-phases of iron nitrides and iron carbides from first principles | Type | A1 Journal article | ||
| Year | 2011 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
| Volume | 64 | Issue |
3 | Pages | 296-299 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | First-principles calculations were performed for the ε-phases and other iron carbides/nitrides with hexagonal close-packed Fe sublattices. Although these nitrides/carbides have similar crystal structures, they exhibit different chemical and physical properties. Relative to α-Fe, graphite and N2, all the ε-type nitrides are stable, while all the carbides are metastable. The lattice parameters of the ε-iron nitrides vary differently from those of the ε-carbides, as a function of the concentration of X (Xdouble bond; length as m-dashN, C). The structural relationships of ε-Fe2X with η-Fe2X and ζ-Fe2X are discussed. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000285323300022 | Publication Date | 2010-09-02 | |
| 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 | 29 | Open Access | |
| Notes | Approved | Most recent IF: 3.747; 2011 IF: 2.699 | |||
| Call Number | UA @ lucian @ c:irua:86974 | Serial | 3120 | ||
| Permanent link to this record | |||||
| Author | Colla, M.-S.; Wang, B.; Idrissi, H.; Schryvers, D.; Raskin, J.-P.; Pardoen, T. | ||||
| Title | High strength-ductility of thin nanocrystalline palladium films with nanoscale twins : on-chip testing and grain aggregate model | Type | A1 Journal article | ||
| Year | 2012 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 60 | Issue |
4 | Pages | 1795-1806 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The mechanical behaviour of thin nanocrystalline palladium films with an ∼30 nm in plane grain size has been characterized on chip under uniaxial tension. The films exhibit a large strain hardening capacity and a significant increase in the strength with decreasing thickness. Transmission electron microscopy has revealed the presence of a moderate density of growth nanotwins interacting with dislocations. A semi-analytical grain aggregate model is proposed to investigate the impact of different contributions to the flow behaviour, involving the effect of twins, of grain size and of the presence of a thin surface layer. This model provides guidelines to optimizing the strength/ductility ratio of the films. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000301989500035 | Publication Date | 2012-02-02 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6454; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 5.301 | Times cited | 38 | Open Access | |
| Notes | Iap | Approved | Most recent IF: 5.301; 2012 IF: 3.941 | ||
| Call Number | UA @ lucian @ c:irua:94213 | Serial | 1465 | ||
| Permanent link to this record | |||||
| Author | Malard, B.; Pilch, J.; Sittner, P.; Delville, R.; Curfs, C. | ||||
| Title | In situ investigation of the fast microstructure evolution during electropulse treatment of cold drawn NiTi wires | Type | A1 Journal article | ||
| Year | 2011 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 59 | Issue |
4 | Pages | 1542-1556 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Microstructural changes taking place during the heat treatment of cold-worked NiTi alloy are of key interest in shape memory alloy technology, since they are responsible for setting the austenite shape and functional properties of the heat-treated alloy. In this work, microstructural evolution during non-conventional electropulse heat treatment of thin NiTi filaments was investigated in a unique high-speed in situ synchrotron X-ray diffraction experiment with simultaneous evaluation of the tensile force and electrical resistivity of the treated wire. The in situ results provide direct experimental evidence on the evolution of the internal stress and density of defects during fast heating from 20 °C to ∼700 °C. This evidence is used to characterize a sequence of dynamic recovery and recrystallization processes responsible for the microstructure and superelastic functional property changes during the electropulse treatments. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000287265100023 | Publication Date | 2010-12-11 | |
| 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 | 48 | Open Access | |
| Notes | Approved | Most recent IF: 5.301; 2011 IF: 3.755 | |||
| Call Number | UA @ lucian @ c:irua:98372 | Serial | 1583 | ||
| Permanent link to this record | |||||