References of "Lecomte-Beckers, Jacqueline"
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See detailMaterials for advanced power engineering 1998 : Proceedings of the 6th Liège conference
Lecomte-Beckers, Jacqueline ULg; Schubert, F.

Book published by Schriften des Forschungszentrum Julich, Reihe energietechnik/Energy Technology Forschungszentrum Julich (1998)

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See detailGraphitization in chromium cast iron
Lecomte-Beckers, Jacqueline ULg; Terziev, L.; Breyer, J. P.

in Mechanical Working and Steel Processing Conference Proceedings (1998)

Some trials with graphite Hi-Cr iron rolls have been done mainly in Japan, for the rolling of stainless steel. This material could lead to good compromise between oxidation, wear and thermal behaviour. By ... [more ▼]

Some trials with graphite Hi-Cr iron rolls have been done mainly in Japan, for the rolling of stainless steel. This material could lead to good compromise between oxidation, wear and thermal behaviour. By using thermal analysis and resistometry, the conditions for secondary graphite formation have been studied. The amount and volume of free graphite may be strongly increased by a suitable heat treatment, allowing a good thermal conductivity as well as high wear and mechanical properties. [less ▲]

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See detailAn elasto-viscoplastic model for forging steel at high temperatures
Charles, J.-F.; Habraken, Anne ULg; Lecomte-Beckers, Jacqueline ULg

in Proceedings of NUMIFORM 98, Simulation of Materials Processing : Theory, Methods and Applications (1998)

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See detailMicrostructure and properties of PM steel reinforced by dispersed oxides and carbides phases
Lecomte-Beckers, Jacqueline ULg; Magnée, Adrien ULg

in Proceedings of ECCM-8, European Conference on Composite Materials : Science, Technologies and Applications (1998)

Two ferrous matrix, a high speed steel and a maraging steel has been reinforced with alumina, titanium and vanadium carbides. The composite was realized by powder metallurgy.The particles were ... [more ▼]

Two ferrous matrix, a high speed steel and a maraging steel has been reinforced with alumina, titanium and vanadium carbides. The composite was realized by powder metallurgy.The particles were mechanically mixed with the prealloyed powder before compaction. To optimize the composite properties, the processing parameters (i.e. prealloyed powders, size, mixing conditions, temperature of sintering, e..) and the effect of reinforcement (size and composition of particles, volume, fraction, ..) were studied. It is necessary to obtain a full density with the minimum porosities and to control boht the size, the distribution and the dispersion of the reinforced particles. The optimal sintering temperature depends on the reinforcement particles used and is of great importance for the properties. Processing parameters (mixing of particules) can greatly affect the final properties. It has been showed that the use of M203 increases the wear resistance in the two matrix. [less ▲]

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See detailModeling of elasto-viscoplastic behaviour of steels at high temperatures
Charles, J. F.; Habraken, Anne ULg; Lecomte-Beckers, Jacqueline ULg

in Baajens; Huetink (Eds.) Proceedings of Simulation of Materials Processing, Methods and Applications. Esaform (1998)

Hot compression tests at constant strain rate and temperature allow to reach stress-strain curves. These experimental data are then used to calibrate a Norton Hoff elastoviscoplastic model (Gavrus ... [more ▼]

Hot compression tests at constant strain rate and temperature allow to reach stress-strain curves. These experimental data are then used to calibrate a Norton Hoff elastoviscoplastic model (Gavrus & Massoni 1995). The implementation of this model (Habraken et al. 1997) in the large strain non linear finite element code LAGAMINE is summarised in this paper. Then finite element thermo-mechanical analysis of previous compression tests and independant ones are performed to validate the produced material constitutive model. These simulations give the stress, strain rate and temperature fields of the sample, necessary to predict recrystallisation phenomena. A summary of the recrystallisation models proposed by the literature as well as the simple one implemented in the LAGAMINA code will be presented. So experimental, numerical and metallographic studies of hot compression tests aim the definition of an accurate predictive thermo-mechanic metallurgical model able to simulate forging processes. [less ▲]

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See detailMatériaux métalliques pour Applications aérospatiales
Lecomte-Beckers, Jacqueline ULg

Learning material (1997)

Propriétés exigées en fonction des sollicitations, température, environnement. Fluage. Fatigue. Corrosion. Mécanismes de durcissement : substitution, précipitation, écrouissage. Conditions particulières d ... [more ▼]

Propriétés exigées en fonction des sollicitations, température, environnement. Fluage. Fatigue. Corrosion. Mécanismes de durcissement : substitution, précipitation, écrouissage. Conditions particulières d'élaboration (vide, électrodes consommables, ESR, etc) et fabrication (solidification dirigée, monocristaux, métallurgie des poudres). Etude des alliages et métaux réfractaires : aciers à haute résistance, superalliages de nickel, cobalt, fer. Molybdène, tantale, niobium, cermets. Alliages légers : aluminium, titane, magnésium. Composites à matrice métallique. Revêtements réfractaires et anti-corrosion. [less ▲]

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See detailDilatometric and calorimetric study of the graphitisation of high chromium cast iron
Terziev, L.; Lecomte-Beckers, Jacqueline ULg; Bojinov, V. et al

in Journal de Chimie Physique et de Physico-Chimie Biologique (1997), 94[5]

Cette étude est consacrée à la formation du graphite dans des fontes à haute teneur en chrome (8%) et spécialement à la détermination des conditions de formation de graphite secondaire par des traitements ... [more ▼]

Cette étude est consacrée à la formation du graphite dans des fontes à haute teneur en chrome (8%) et spécialement à la détermination des conditions de formation de graphite secondaire par des traitements thermiques adaptés. La solidification de la fonte étudiée a été examinée par analyse thermique différentielle (ATD). Les effets d'un traitement à haute température ont été examinés à la fois par calorimétrie et dilatomètre différentielle. Le graphite primaire se forme vers 950°C. Le graphite secondaire précipite sur le graphite primaire lors du traitement de déstabilisation de l'austénite à haute température. La forme et la quantité de graphite secondaire dépendent de la température de traitement. [less ▲]

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See detailStudy of graphite precipitation during heat treatment in chromium cast iron
Lecomte-Beckers, Jacqueline ULg; Terziev, L.

in Proceeding of the Annual Meeting of the SBM/NMVS (1997)

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See detailComportement des matériaux métalliques utilisés dans les systèmes énergétiques
Lecomte-Beckers, Jacqueline ULg

Learning material (1996)

Matériaux métalliques - mécanismes de déformation, modes de durcissement. Liaison entre microstructure et propriétés, schématisation des comportements réels. - Matériaux pour turbine à vapeur (aciers ... [more ▼]

Matériaux métalliques - mécanismes de déformation, modes de durcissement. Liaison entre microstructure et propriétés, schématisation des comportements réels. - Matériaux pour turbine à vapeur (aciers faiblement alliés - aciers 9-12% Cr - aciers fortement alliés). - Matériaux pour systèmes énergétique avancé (alliages ODS). Matériaux pour turbines à gaz (superalliages - intermétalliques - Titane - solidification dirigée - monocristal). - Evaluation des défauts en service. - Prédiction de la durée de vie. - Corrosion et revêtements (TBC). - Endommagement : rupture brutale, fluage et fatigue, corrosion sous tension. - Visite d'une installation. [less ▲]

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See detailProtection contre la corrosion
Lecomte-Beckers, Jacqueline ULg

Learning material (1996)

Aspect phénoménologique des attaques de corrosion. - Thermodynamique des réactions de corrosion. - Surfaces et interfaces. - Vitesse des réactions de corrosion. - Passivité des métaux. - Mécanismes de ... [more ▼]

Aspect phénoménologique des attaques de corrosion. - Thermodynamique des réactions de corrosion. - Surfaces et interfaces. - Vitesse des réactions de corrosion. - Passivité des métaux. - Mécanismes de corrosion (piles - piqûres - corrosion galvanique). - Oxydation et corrosion atmosphérique. - Corrosion à haute température. - Corrosion-érosion - Corrosion microbiologique. - Fissuration sous contrainte. - Protection contre la corrosion; critères de choix. - Importance de la corrosion dans l'industrie - cas particuliers. [less ▲]

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See detailCorrosion des Matériaux métalliques
Lecomte-Beckers, Jacqueline ULg

Learning material (1995)

Aspect phénoménologique des attaques de corrosion. - Thermodynamique des réactions de corrosion. - Surfaces et interfaces. - Vitesse des réactions de corrosion. - Passivité des métaux. - Mécanismes de ... [more ▼]

Aspect phénoménologique des attaques de corrosion. - Thermodynamique des réactions de corrosion. - Surfaces et interfaces. - Vitesse des réactions de corrosion. - Passivité des métaux. - Mécanismes de corrosion (piles - piqûres - corrosion galvanique). - Oxydation et corrosion atmosphérique. - Corrosion à haute température. - Corrosion-érosion - Corrosion microbiologique. - Fissuration sous contrainte. - Protection contre la corrosion; critères de choix. - Importance de la corrosion dans l'industrie - cas particuliers. [less ▲]

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See detailInfluence of creep on the microstructure of Zn-Al-Cu alloys aged at 250°C
Terziev, L.; Lecomte-Beckers, Jacqueline ULg; Wegria, J.

in Physica Status Solidi A : Applied Research (1995), 152[2]

This paper is a continuation of a microstructural study of ZA alloys subjected to ageing at different temperatures with subsequent creep at 20 and 120 °C. it was already established that the samples aged ... [more ▼]

This paper is a continuation of a microstructural study of ZA alloys subjected to ageing at different temperatures with subsequent creep at 20 and 120 °C. it was already established that the samples aged for one week at 100 and 250 °C show the slowest creep rate. Furthermore, the resuits obtained afler ageing at 250 °C are better than those obtained after ageing at 100 °C. In order to explain more correctly these resuits, the microstructure is studied after ageing at 250 oc and subsequent creep at room temperature under pressure at 100 MPa and at 120 °c under pressure at 40 MPa, on test samples broken after the respective creep. [less ▲]

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See detailEffect of microstructural transformation on the creep resistance of Zn-Al-Cu alloys
Lecomte-Beckers, Jacqueline ULg; Terziev, Luben

in Proceedings of Trinocular Joint Meeting on Electron Microscopy (1995)

This paper illustrates the modification of the structure induced by creep treatments. The aim of this study is to compare the evolution of the structure after creep tests on samples treated at 100°C and ... [more ▼]

This paper illustrates the modification of the structure induced by creep treatments. The aim of this study is to compare the evolution of the structure after creep tests on samples treated at 100°C and 250°C. Creep tests have been carried out at 120°C with a tensile stress of 40 MPa and at 20°C with a tensile stress of 100 MPa. [less ▲]

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See detailMicrostructural study of a zinc-aluminium-copper alloy after thermal treatment at 100°C and creep
Terziev, L.; Lecomte-Beckers, Jacqueline ULg; Wegria, J.

in Zeitschrift für Metallkunde (1994), 85[9]

The creep behaviour of the ternary Zn—A1—Cu alloy after thermal treatment at ioo oc has been studied. The applied creep stress does flot modify clearly the transition phases (OL, T% ‘11m) appearing during ... [more ▼]

The creep behaviour of the ternary Zn—A1—Cu alloy after thermal treatment at ioo oc has been studied. The applied creep stress does flot modify clearly the transition phases (OL, T% ‘11m) appearing during isothermal ageing. During the creep test, the formation of an important density of defects resuits in the precipitation of T’ and O’ particles. The quantity of these phases depends on the creep conditions. [less ▲]

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See detailEtude des relations entre les microstructures obtenues par vieillissement isotherme et le comportement mécanique (fatigue, résilience) dans des alliages Zn-Al et Zn-Al-Cu
Lecomte-Beckers, Jacqueline ULg; Terziev, L.; Wegria, J.

in Revue de Métallurgie [=Revue de Métallurgie. Cahiers d'Informations Techniques] (1994), 91[5]

L’article présenté établit une corrélation entre le comportement mécanique (fluage, résilience) et les microstructures qui apparaissent au cours d’un traitement thermique isotherme (100 ou 250 °C) dans ... [more ▼]

L’article présenté établit une corrélation entre le comportement mécanique (fluage, résilience) et les microstructures qui apparaissent au cours d’un traitement thermique isotherme (100 ou 250 °C) dans des alliages Zn-Al et Zn-Al-Cu1. Le but est de mettre en évidence l’intérêt pratique des modifications structurales obtenues. On observe un meilleur résultat pour des échantillons vieillis pendant une semaine environ. La température de traitement la plus favorable est 250 °C. De plus, les alliages contenant du cuivre possèdent un meilleur comportement que les alliages binaires Zn-Al. [less ▲]

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See detailEffect of isothermal ageing on the Zn-Al alloys creep characteristics
Lecomte-Beckers, Jacqueline ULg; Terziev; Wegria et al

in Proceedings of The 3rd International Conference on Zn-Al Alloys - Advances in Science, Technology and Applications of Zn-Al Alloys (1994)

The aim of this study is to correlate the creep parameters of aged Zn-Al samples with the microstructure developed during heat treatment, and to point out the practical interest of such microstructure ... [more ▼]

The aim of this study is to correlate the creep parameters of aged Zn-Al samples with the microstructure developed during heat treatment, and to point out the practical interest of such microstructure modifications. Two different isothermal ageings were carried out at 100°C and at 250°C for different periods of times (from 30 min. to 8 weeks). During those ageings, complex precipitations occur. The decomposition of the initial supersaturated solid solution begins with a cellular reaction leading to cfc and hcp lamellar. The cfc phase decomposes into transition phases. The ageing temperature (100 or 250°C) influences the decomposition stages. Creep testson aged samples reveal the influence of the microstructure developed during the heat treatment at 100 or 250°C. An improvement of the creep properties by one order of magnitude can be observed when the sample exhibits the appropriate structure. [less ▲]

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See detailMechanical properties and recrystallisation behaviour of Fe base ODS alloys
Lecomte-Beckers, Jacqueline ULg; Coutsouradis, D.; Lecomte-Mertens, Ch. et al

in Proceedings of PM'94, Congrès mondial de Métallurgie des Poudres (1994)

Developments in higher temperature exchangers and other applications require high strength as well as oxidation resistance at very high temperature. In order to meet such requirements, Dour Metal has ... [more ▼]

Developments in higher temperature exchangers and other applications require high strength as well as oxidation resistance at very high temperature. In order to meet such requirements, Dour Metal has developed ODM new range of oxide dispersion strengthened (ODS) iron base alloys realised by powder mechanical alloying. Compositional and thermomechanical manipulations can be used to develop the structure enabling the service temperature to be increased up to about 1200°C. An optimization of the structure is required to obtain the best high temperature creep resistance. This consist in minimizing the grain densities and the misorientation between adjoining grains. The paper will discuss some results on evolution of the texture during different thermomechanical treatments on ODS Fe base tubes. Typical rupture strength will be presented for temperature ranging from 900 to 1100°C. The emphasis will be given to alloy ODM 751 which most recent work has been performed. [less ▲]

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See detailRecrystallisation behaviour of Fe base ODS alloys
Lecomte-Beckers, Jacqueline ULg; Coutsouradis, D.; Kazimierzak, B.

in Proceedings of the International Conference on Materials for Advanced Power Engineering (1994)

Developments in higher temperature exchangers and other applications require high strength as well as oxidation resistance. In order to meet such requirements, Dour Metal has developed the 0DM new range ... [more ▼]

Developments in higher temperature exchangers and other applications require high strength as well as oxidation resistance. In order to meet such requirements, Dour Metal has developed the 0DM new range of oxide dispersion strengthened (ODS) iron based alloy. Compositional and thermomechanical manipulations can be used to develop the structure enabling (be service temperature to be increased up W about 1200°C. In both Ni and Fe base ODS materials, an optimization of the structure is required to obtain the best high temperature creep resistance. This consists in minimizing the grain boundaries density and misorientation between adjoining grains. ODS Fe base alloys and Ni base alloys differ as follows: - for alloys with high stacking fault energy (as ferritic steel) the phenomenon involved during hot deformation is dynamic recovery - for alloys with low stacking energy (as Ni alloys and austenilic steels) the phenomenon is dynamic recrystallization. The texture obtained during recovery is weIl marked and leads to 10w angle boundaries. A static treatment in bot furnace is then enough to develop the secondary dynamic recrystallization. Dynamic recrystallization leads to randomly oriented grains with high angle boundaries. A secondary dynamic recrystallization is then more difficult and oriented recrystallization leading to an oriented texture must be favoured by creating a thermal gradient during the treatment. The paper discusses some results on (lie evolution of the texture during treatments on ODS Fe base alloy tubes. It is pointed out that to obtain the temperature, it is important to control the thermomechanical treatments from recrystallization treatment. [less ▲]

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See detailEvolution of microstructure during creep of thermally treated Zn-Al-Cu alloy
Lecomte-Beckers, Jacqueline ULg; Terziev, L.; Wegria, J.

in Proceedings of the 13th International Congress on Electron Microscopy (1994)

This paper illustrates the modifications of the structure induced by creep treatments. The aim of this study is to compare the evolution of the structure after creep tests on samples treated at 100°C and ... [more ▼]

This paper illustrates the modifications of the structure induced by creep treatments. The aim of this study is to compare the evolution of the structure after creep tests on samples treated at 100°C and 250°C. Creep tests have been carried out at 120°C with a tensile stress of 40MPa and at 20°C with a tensile stress of 100MPa. [less ▲]

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See detailMatériaux métalliques spéciaux
Lecomte-Beckers, Jacqueline ULg

Learning material (1993)

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