References of "Lecomte-Beckers, Jacqueline"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailHIGH TEMPERATURE CORROSION RESISTANCE OF METALLIC MATERIALS IN HARSH CONDITIONS
Novello, Frederic; Dedry, Olivier ULg; De Noose, Vincent et al

in Lecomte-Beckers, Jacqueline; Dedry, Olivier; Oakey, John (Eds.) et al Proceedings of the 10th Conference on Materials for Advanced Power Engineering 2014 (2014, September)

Highly efficient energy recovery from renewable sources and from waste incineration causes new problems of corrosion at high temperature. A similar situation exists for new recycling processes and new ... [more ▼]

Highly efficient energy recovery from renewable sources and from waste incineration causes new problems of corrosion at high temperature. A similar situation exists for new recycling processes and new energy storage units. These corrosions are generally considered to be caused by ashes or molten salts, the composition of which differs considerably from one plant to another. Therefore, for the assessment of corrosion-resistance of advanced materials, it is essential to precisely evaluate the corrosion rate under conditions close to industrial conditions. To be able to advise their customers in selecting the right material or the right protective coating, the present authors are developing testing equipment and related procedures to assess the high temperature corrosion rate of metallic materials. This paper describes the testing equipment developed so far and presents the first results obtained in two corrosive environments: the aggressive condensates that affect waste incinerators (mixture of liquid/solid salts in oxidising conditions) and heat transfer fluids of electric power generating plants based on solar towers (mixture of liquid salts). Temperatures range from 400 to 650°C. Tested materials include 16Mo3 (0.3% molybdenum steel alloy), Inconel 625 (austenitic nickel-chromium-based superalloys), Nickel 200, Ni-57CrMoSiB (nickel-base coating with high chromium content and boron as additional element) and Grade 91 (9% chrome- 1% molybdenum steel alloy). [less ▲]

Detailed reference viewed: 123 (2 ULg)
Full Text
See detailProceedings of the 10th Conference on Materials for Advanced Power Engineering 2014
Lecomte-Beckers, Jacqueline ULg; Dedry, Olivier ULg; Oakey, J. et al

Book published by FZ. Juelich (2014)

The 10th Liege Conference on Materials for Advanced Power Engineering presents the achievements of international materials related research for high e ciency, low-emission power plants. Furthermore the ... [more ▼]

The 10th Liege Conference on Materials for Advanced Power Engineering presents the achievements of international materials related research for high e ciency, low-emission power plants. Furthermore the new demands of the transition of electricity supply towards more and more regenerative power sources are reported. Resource preservation and maximization of economic success by improved plant e - ciency were the driving forces in past materials and power plant technology development. Fossil fuels will still play a considerable role for future energy security, even if renewables gain rising importance. The integration of uctuating renewable energy technologies poses great future challenges in terms of load exibility, thermal cycling capability and downtime corrosion resistance for the materials employed in new concentrated solar power, biomass red or gas to liquid plants and the backing conventional fossil red power plants. In order to balance erroneous availability forecasts of uctuating regenerative power sources (wind, solar) and vice versa to bridge short periods of low conventional power demand, the minimum load capability of conventional power plants will have to be decreased, while on the other hand start-up times and load ramps will have to be increased to ensure grid stability. Above all improved e ciency of plant, implying rising process temperatures and pressures remains of the utmost importance to ensure economic prosperity. All these issues will create even stronger demands for future materials research and development. The series of Liège Conferences on Materials for Advanced Power Engineering re ects the necessity of joint international material research and component development for critical components of power generation equipment by bringing together material scientists, design engineers, alloy producers and component manufacturers. To put European efforts into an international framework there are several invited research and review papers covering materials, component and process development in the USA and Asia. In addition there are more than 75 contributed papers from 22 countries which are presented as posters at the conference. [less ▲]

Detailed reference viewed: 180 (12 ULg)
Full Text
See detailRapport Final - PROJET ULTRA CB - CONVENTION RW 6418 : Etude de faisabilité dans le développement de nano-revêtements sol-gels capables d’assurer une protection anticorrosion dans les applications soumises à des contraintes mécaniques et thermiques
Lecomte-Beckers, Jacqueline ULg; Dedry, Olivier ULg

Report (2014)

Ce rapport final s’inscrit dans le cadre du projet ULTRA-CB porté par Saint Roch Couvin SA. Le but de ce projet est de réaliser une étude de faisabilité dans le développement de nano-revêtements sol-gels ... [more ▼]

Ce rapport final s’inscrit dans le cadre du projet ULTRA-CB porté par Saint Roch Couvin SA. Le but de ce projet est de réaliser une étude de faisabilité dans le développement de nano-revêtements sol-gels capables d’assurer une protection anticorrosion dans les applications soumises à des contraintes mécaniques et thermiques. L’objectif pour Saint Roch Couvin (SRC) est d’appliquer les résultats de cette recherche industrielle sur un substrat de fonte au travers d’une étude de faisabilité d’une chaudière en fonte à condensation interne. [less ▲]

Detailed reference viewed: 58 (1 ULg)
Full Text
See detailCharacterization of the Solidification Path, the Solid State Transformations and the Mechanical Behavior of a High Chromium Cast Steel
Tchuindjang, Jérôme Tchoufack ULg; Neira Torres, Ingrid; Habraken, Anne ULg et al

in Proceedings of the 5th Abrasion Conference - 2014 (2014, August)

The mechanical behavior of the fully austenitic matrix of a High Chromium Cast Steel (HCCS) alloy has been determined under external compression stress applied at 300°C and 700°C. The solidification path ... [more ▼]

The mechanical behavior of the fully austenitic matrix of a High Chromium Cast Steel (HCCS) alloy has been determined under external compression stress applied at 300°C and 700°C. The solidification path and the microstructure have been studied, including the nature and the critical temperature ranges for carbides formation, while using Differential Thermal Analysis and both Optical and Scanning Electron Microscopes. The microstructure has been characterized towards both Optical and SEM analyses. Differential Thermal Analysis and Dilatometry were used to study the solid state phase transformations on the one hand, and precipitation and dissolution reactions on the other hand, especially during heating from room temperature up to austenitization, and subsequent cooling down to room temperature. Dilatometry also helps setting the parameters for the preliminary thermal treatments to perform prior to compression tests, in order to allow more or less transition carbides within the stressed microstructure, the other carbides remaining undissolved. Flow stress curves and related work hardening rates were determined for both temperatures. From the compression tests, various strengthening phenomena, such as precipitation hardening and stress induced bainite transformation, and one softening mechanism such as recovery, have been highlighted, while enhancing at the same time the influence of the temperature and the carbide type on the mechanical behavior of the HCCS material. Cracks observed on grain boundaries primary carbides allow establishing a rough damage model. The crack initiation within the HCCS alloy seems to be strongly dependent on the temperature, the external applied stress and the matrix toughness. [less ▲]

Detailed reference viewed: 43 (12 ULg)
Full Text
See detailProcessing metallic materials by additive technologies - Specificities of the thermal history and microstructures
Mertens, Anne ULg; Lecomte-Beckers, Jacqueline ULg

Conference given outside the academic context (2014)

Additives technologies currently attract a growing interest as they are particularly versatile and well adapted for the production of small series e.g. of metallic parts. Beyond the great diversity of the ... [more ▼]

Additives technologies currently attract a growing interest as they are particularly versatile and well adapted for the production of small series e.g. of metallic parts. Beyond the great diversity of the concerned processes (laser beam melting, electron beam melting, laser cladding…) and metallic alloys, some common features may be highlighted: (1) the strong directionality of additive processes, due to the fact that parts are fabricated “layer-by-layer”; (2) the ultra-fast heating and cooling cycles, following the displacement of the beam(s) away from the working zone. The present paper aims at illustrating these two major features of additive techniques through case studies involving the most common metallic alloys (steels, Al- or Ti-based alloys…), thus highlighting the opportunities pertaining to additive technologies for the optimisation of materials microstructures and of the resulting properties. [less ▲]

Detailed reference viewed: 60 (15 ULg)
Full Text
See detailLes composites à matrice métallique/céramique – De nouveaux procédés de fabrication pour de nouvelles applications
Mertens, Anne ULg; Lecomte-Beckers, Jacqueline ULg

Conference (2014, May 20)

A l’heure où la plupart des matériaux composites essentiellement structuraux sont faits d’une matrice à base polymère, les matériaux composites à matrice métallique ou céramique offrent de nouvelles ... [more ▼]

A l’heure où la plupart des matériaux composites essentiellement structuraux sont faits d’une matrice à base polymère, les matériaux composites à matrice métallique ou céramique offrent de nouvelles perspectives en termes de performances et de durabilité. Le présent exposé s’attache plus particulièrement à retracer les possibilités offertes par de nouvelles méthodes de mise en oeuvre telles que la friction-malaxage et les techniques d’impression 3D, aussi bien en termes d’amélioration des propriétés mécaniques des matériaux composites que des fonctionnalités inédites qui peuvent leur être conférées. [less ▲]

Detailed reference viewed: 96 (15 ULg)
Full Text
See detailProcessing of alloy Ti-6Al-4V and of stainless steel 316L by Laser Beam Melting
Mertens, Anne ULg; Paydas, Hakan ULg; Reginster, Sylvie ULg et al

Conference (2014, May)

Additive manufacturing processes such as Selective Laser Melting (SLM) appear very promising in view of the economic production of near-net-shape, complex and (almost) fully dense parts from metallic ... [more ▼]

Additive manufacturing processes such as Selective Laser Melting (SLM) appear very promising in view of the economic production of near-net-shape, complex and (almost) fully dense parts from metallic materials such as Ti alloys and stainless steels. Practically, in SLM, a metallic powder is deposited layer-by-layer in a powder bed and then molten locally according to the desired shape. An important feature of this process is that the structure undergoes an ultra-fast cooling once the beam leaves the working zone, thus giving rise to strongly out-of-equilibrium microstructures. In the case of Ti alloy Ti-6Al-4V, in particular, the microstructural anisotropy resulting from the epitaxial growth of the newly deposited layer on the material previously solidified has been shown to exert a very strong influence on the mechanical properties [1] In the present work, the thermophysical behaviour of Ti-alloy Ti-6Al-4V and of stainless steel 316L has been characterised in details, in order to reach a better understanding of the phenomena controlling the microstructures and mechanical properties of parts. In particular, the thermal conductivity of Ti-alloy Ti-6Al-4V and of stainless steel 316L at high temperature has been determined by combining dilatometry, Differential Scanning Calorimetry (DSC) and laser flash diffusivimetry based on Laplace’s equation. Since Ti-alloy Ti-6Al-4V and stainless steel 316L exhibit quite different physical behaviours, their careful comparison is shown to shed more light into the role of phenomena such as epitaxial growth, out-of-equilibrium phase transformations and/or internal stresses in the additive manufacturing of metallic materials. [less ▲]

Detailed reference viewed: 118 (20 ULg)
Full Text
See detailTechniques additives vs techniques conventionnelles-les microstructures
Mertens, Anne ULg; Lecomte-Beckers, Jacqueline ULg

Conference given outside the academic context (2014)

Très flexibles et particulièrement bien adaptées à la production de petites séries, les techniques additives suscitent un intérêt croissant, notamment pour la mise en oeuvre de matériaux métalliques. Par ... [more ▼]

Très flexibles et particulièrement bien adaptées à la production de petites séries, les techniques additives suscitent un intérêt croissant, notamment pour la mise en oeuvre de matériaux métalliques. Par-delà la diversité des techniques que ce terme recouvre (laser beam melting, electron beam melting, laser cladding…) et par-delà la variété des alliages qu’elles permettent de mettre en oeuvre, quelques caractéristiques récurrentes se dessinent: 1) La nature fortement directionnelle des procédés additifs, lié au fait que la pièce est fabriquée “couche par couche” 2) Des cycles de chauffe et de refroidissement ultra-rapides, en fonction des déplacements du/des faisceau(x) La présente communication s’attache à illustrer ces deux caractéristiques essentielles des techniques additives au moyen d’exemples touchant aux principaux alliages métalliques (aciers, alliages d’aluminium ou de titane…), et à en dégager les risques et les opportunités qu’offrent les techniques additives du point vue du contrôle et de l’optimisation des microstructures et des propriétés d’usage qui en découlent… [less ▲]

Detailed reference viewed: 67 (12 ULg)
Full Text
Peer Reviewed
See detailMicrostructures and Mechanical Properties of Stainless Steel AISI 316L Processed by Selective Laser Melting
Mertens, Anne ULg; Reginster, Sylvie ULg; Contrepois, Quentin et al

in Materials Science Forum (2014), 783-786 (2014)

In this study, samples of stainless steel AISI 316L have been processed by selective laser melting, a layer-by-layer near-net-shape process allowing for an economic production of complex parts. The ... [more ▼]

In this study, samples of stainless steel AISI 316L have been processed by selective laser melting, a layer-by-layer near-net-shape process allowing for an economic production of complex parts. The resulting microstructures have been characterised in details in order to reach a better understanding of the solidification and consolidation processes. The influence of the processing parameters on the mechanical properties was investigated by means of uniaxial tensile testing performed on samples produced with different main orientations with respect to the building direction. A strong anisotropy of the mechanical behaviour was thus interpreted in relation with the microstructures and the processing conditions. [less ▲]

Detailed reference viewed: 169 (16 ULg)
Full Text
See detailRapport Final, Projet FEDER Programmation 2007-2013, portefeuille de projets SINUS : Simulation Numérique Haute Performance
Lecomte-Beckers, Jacqueline ULg; Mertens, Anne ULg; Carton, Marc et al

Report (2014)

Le portefeuille de projets SINUS : Simulation Numérique Haute Performance, s'inscrit dans le cadre des mesures 2.2 de valorisation du potentiel des centres de recherche en Wallonie. Trois projets ... [more ▼]

Le portefeuille de projets SINUS : Simulation Numérique Haute Performance, s'inscrit dans le cadre des mesures 2.2 de valorisation du potentiel des centres de recherche en Wallonie. Trois projets composent le portefeuille SINUS: une action 2.2.1 Équipements technologiques exceptionnels, une action 2.2.2 Projets de recherche transversaux en partenariat, une action 2.2.4 Optimisation de l'offre de services technologiques des centres de recherches agréés.Ce rapport s'inscrit dans l'action 2.2.2 des projets de recherche transversaux en partenariat. Cette action vise à développer des méthodes numériques de nouvelle génération en collaboration avec des centres de recherche universitaires et agréés et des entreprises répondant aux besoins de l’industrie. Les domaines couverts sont la modélisation des processus de fabrication, des matériaux et des structures, la mécanique des fluides et l’optimisation multidisciplinaire. Au sein de cette action, différents lots ont été définis : Lot 1 Modélisation avancée d'écoulements complexes multi-physiques, Lot 2 Modélisation avancée multi-échelles des matériaux et des structures, Lot 3 Modélisation avancée des procédés de fabrication, Lot 4 Optimisation multidisciplinaire. [less ▲]

Detailed reference viewed: 38 (5 ULg)
Full Text
Peer Reviewed
See detailStudy of residual stresses in bimetallic work rolls
Neira Torres, Ingrid ULg; Gilles, Gaëtan ULg; Tchuindjang, Jérôme Tchoufack ULg et al

in Advanced Materials Research (2014), 996

An experimental campaign of compression tests, differential thermal analysis (DTA), differential scanning calorimetry ( DSC), dilatometry and microstructure analysis has been performed, as well as the ... [more ▼]

An experimental campaign of compression tests, differential thermal analysis (DTA), differential scanning calorimetry ( DSC), dilatometry and microstructure analysis has been performed, as well as the identification of the material data set for finite element ( FE) analysis of bimetallic rolls. This article numerically investigates the stress and strain fields after the cooling stage and it checks their effect on the subsequent heat treatment step. As bimetallic rolls have a different material for core and shell, the effect of the roll size and the shell thickness on residual stresses is also studied. [less ▲]

Detailed reference viewed: 88 (27 ULg)