Activités de recherche

§ Characterisation of mechanical and thermal hot properties

Description: The thermophysical properties of pure metals or alloys have been widely studied by the metallurgy industries, giving them the data needed for the simulation, but also for a better scientific understanding of different physical process. Today, the simulations of material forming process are powerful and irreplaceable tools for the design and the modelling of new pieces, for the automotive industry, for example. So, there is a constant need of thermophysical data more and more accurate on known material as well as data on new alloys. The laboratory of the sector MMS is specially equipped to study phase transformation and measuring thermophysical properties (a, l, Cp…) and studying microstructure of materials. ATD – DSC – TG (1500°C) – dilatometry (1500°C) – laser flash (2000°C) - optical microscopes - metallographic preparation - thermal treatment furnace and quench devices.

Publications: MMS102, MMS126, MMS101, MMS129, MMS128, MMS131, MMS108, MMS109, MMS112, MMS105

Research staff involved: M. CARTON

Partners: Aleurope, Hydroaluminium-Raeren, Sonaca, UCA, TAC, Focast, Fafer, CFR, CMI, MSM (A.M. Habraken, S.Cescotto) (University of Liège)

Related project: RW Convention 9813793 caract. à chaud; Contracts: UCA, Gonterman Peipers, Arselor Sollac méditerranée, OCAS, Akers

§ Effect of carbides and inclusions in high alloyed irons and steels

Description: The goal of this project is to define the relationship between micro and macroscopic material properties that can be used in the simulations of the rupture mechanisms. A rigorous set of experiences must be planned and quantitative micro- as well as macroscopic techniques is required.

This project is interested in steels and high alloyed cast irons and is focused on the quantitative and statistical relationship between, on one side, the inclusions property, the amount of carbides and the microstructure and, on the other side, on the mechanical properties. This research is based on the methodology experimented in a previous project. This previous research was built on the development of experimental micro- and macroscopic techniques.

One of the main points is the size of the carbides and the inclusions, which makes it tough to detect them by classical microscopic imagery. So, other methods have to be developed.

In this project, the focus has been made on the diversity of the materials examined above the number of experiment made on each.

Publications: MMS103, MMS118, MMS114, MMS115, MMS111, MMS134, MMS135, MMS119, MMS136, MMS137, MMS130, MMS104, MMS116

Research staff involved: J. TCHOUFANG TCHUINDJANG

Partners: Forcast, Marichal Ketin, MSM (AM Habraken, S.Cescotto) (University of Liège), MICA ( E.Pirard) (University of Liège)

Related project: “Study of carbides forming elements in alloys type HSS and semi-HSS”, “Effect of carbides and inclusions in high alloyed irons and steels”, Convention RW 114877 INCA

§ Development of new alloys for hot rolls

Description: .The hot rolling mill is a massive piece that endures high service solicitation like thermal and mechanical constraints as well as fatigue or usury. The rolled product quality and the productivity of the process are directly related to the quality of the working mills.

The goal of this project is to enhance the knowledge in this sector and particularly to study the kinetic of the precipitation and the formation of the carbides required for a good quality of the product. Additional studies on surface corrosion will be done at the Complutense University in Madrid.

This approach is essential to define the optimal structure leading to the highest life span of the mills.

Publications: MMS120, MMS121, MMS117, MMS138, MMS1222, MMS123

Research staff involved: M. HERMAN

Partners: Marichal Ketin

Related project: “Study of carbides forming elements in alloys type HSS and semi-HSS”, Convention RW-MARICHAL KETIN 3967, 4524, 6060, DGRE - DRI - Project N0 01-10898 “Study of precipitation in foundry alloys type HSS” AND “Kinetic of phase transformations in foundry alloys for rolls type ICDP”

§ Thixomoulding

Description: Semi-solid metals exhibit time and strain rate dependent behavior known as thixotropy: they behave like solids in the undisturbed state and like liquids during shearing provided the shear rate is high enough. The solid-like behavior is due to the presence of a solid skeleton consisting of interconnected grains. Shearing breaks the bonds between grains leading to a release of entrapped liquid and decreasing the viscosity of the semi-solid alloy. Semi-solid metal forming called thixoforming exploits this thixotropic and shear-thinning behavior since the semi-solid slug may be handeable but also may flow easily in the die. The use of FE simulations to obtain the filling of the dies and to optimize the thixoforming process is clearly of a great interest.

The aim of this project is to write a new micro-macro constitutive equation that describes the semi-solid behavior. This will be made in two fronts: The first one is to plan a set of experiments in order to determine the parameters of this law for steels; the second one is to implement the new material law in the METAFOR FE code.

Publications: MMS113

Research staff involved: R. KOEUNE

Partners: CRIF,ULG,Pôle métal de Wallonie, ELAP (W. Legros, A.Rassili) (University of Liège), MC et thermomécanique ( JP. Ponthot) (University of Liège)

Related project: Subvention objectif 2- URBAIN Meuse-Vesdre Moyens, Contract Ascométal

Description: The main goal of this project is to develop a new material based on an existing alloy: Ti-LCB, but with better fatigue damaging properties and sufficient ductility.

First, the characterisation and the understanding of the relationships between the thermo mechanical history and the fatigue structural properties will be established. So, on one side, the construction of the microstructure along the thermo mechanical path, implying allotropic transformation or phenomena like rehabilitation, recrystallisation and grain growth, will be studied. On the other side, the microscopic mechanisms leading to the structural properties of this alloy, like tenacity, fatigue resistance and cyclic plasticity will be examined.

Another objective is to implement this knowledge into micro mechanical models. The project will focus on a physical based model able to predict the fatigue resistance of biphasic-Ti-alloys with thin grains.

The third goal is the validation of the model based on real loading studies.

Publications:

Research staff involved: M. CARTON

Partners: Tech Space Aero, MSM ( AM Habraken, S.Cescotto) (University of Liège)– University Catholic of Louvain ( PCIM Pascal jacques)

Related project: Convention RW 415659

§ Fabrication of metallic foils by vacuum deposition – First Spin Off

Description: Metallic foils have proved to be useful in many fields like packaging or magnetic products. So far, the foils have been mainly produced by rolling in the case of soft materials like aluminium, or by electrolysis in the case of metals like copper. Those process do not give the surface quality required, so the foils must be treated by PVD (Physical Vapour Deposition) afterwards.

In this project, a technique of SIP (Self-induced Ion Plating) is proposed. This technique would be able to realise foils with good surface quality in one step. The SIP process is a combination of cathodic pulverisation process and evaporation. Its main advantage is the high deposition rate and the good quality of the deposit.

In the actual state of the research, the goal is not yet to realise composite materials, but to look at the possibilities to achieve thin coatings of the materials that the composite will be made of.

Publications:

Research staff involved: S. PACE

Partners: RdCs

Related project: Convention RW – EVAFOIL – 415810

Description: This project attempts to set a micro-macro model of the hot damaging behaviour. Most of damaging models established so far are ductile cold rupture, fragile rupture, fatigue or creep. All are valid at low temperatures.

For monotone solicitations at very high temperatures, the damage process is fast creep or diffusion creep. The present project is focused on this particular phenomenon.

The industrial application is the simulation of the continuous casting and particularly the areas where cracking can start.

The final goal of this research is the definition of rupture criteria coupled with a macroscopic damaging model. Those criteria should be able to predict the cracking for any kind of solicitation and the origins of the cracking will be analysable.

Publications: MMS102, MMS127

Research staff involved: J. TCHOUFANG TCHUINDJANG

Partners: CDAM de Cockerill-Sambre-Usinor, MSM (A.M. Habraken, S. Cescotto, S. Castagne) (University of Liège)

Related project: ULg grants, “Micro-macro study of high temperature damage in steels”, “Study of carbides forming elements in alloys type HSS and semi-HSS”

§ Macrofoams, a new material for security in civil engineering

Description: Study and development of macro cellular foams obtained from cheap metallic components, in particular from recycled material (chips from machining, metallic wires, expanded metal sheets, …): study of possible topologies, analysis of fabrication possibilities, determination and modelling of mechanical, thermal and acoustic properties. Applications in the domain of safety and robustness of buildings (resistance to explosives, anti-intrusion walls, seismic resistance, …) or others (new types of safety barriers along the roads, light armour plating for money transporting cars, shock absorbers for parachuted material or for nuclear waste transportation boxes, …)..

Publications:

Research staff involved: J. TCHOUFANG TCHUINDJANG

Partners: University of liège : Division of Mécanique des Solides et des Matériaux -MSM- (CESCOTTO Serge), Division of l’Ingéniérie Sismique –SE- (PLUMIER André), Division of l’Ingéniérie du Feu –FE- (FRANSSEN Jean-Marc), Division of Cellule d’Etudes et de Développement en Ingéniérie Acoustique –CEDIA- (NEMERLIN Jean)

Related project: CF – concerted action, “Macrofoams, a new material for security in civil engineering”

Description: Forging and related metal forming processes are key industrial technologies since they are required to produce economically many highly reliable parts. Over the last decades, these industrial processes have been improved through many RTD projects in materials science, mechanical engineering and more recently in numerical simulation. The goal of ViF-CA is to gather and analyse this scattered knowledge in order to solve some of today's industrial problems and to incorporate into industrial practices the recent advances in virtual production, supply chain and life-cycle management. The strategy is to create a forging knowledge community through several scientific, technological, training and educational activities.

The consortium gathers educational and research organisations, experts in the various scientific areas, and a large number of forging, software and IT industries from 17 European countries. The Deliverables include a Book of forging, projects for an e-Database and an e-learning platform, benchmarks for process simulations and materials testing, and a structure for a virtual supply chain.

Publications:

Research staff involved: R. KOEUNE

Partners: MSM (A.M. Habraken) (University of Liège)

Related project: Convention NMP2-CT-2004-507331

§ Non-contact Ultrasonic sytem for rail track inspection (U-RAIL)

Description: Periodic in-track rail inspections are performed to detect critical defects before they grow enough to cause structural failure. Nondestructive inspection (NDI) technologies currently used worldwide rely mainly on conventional ultrasonic technologies. These use water filled rubber wheels, containing transmitter-receiver piezoelectric transducers, that are kept in continuous contact to the rail running surface. These methods have limitations, as they require contact conditions between the inspection probes and the surface of the rail track. Although such contact ultrasonic methodologies have been extensively and successfully used in detecting many surface-breaking and internal cracks, and are proved to be reliable, they are not perfect. In fact, train derailments caused by broken rails that pass inspection still occur.

In an effort to improve rail track inspections, this project proposes a non-contact ultrasonic system for periodic in-field inspections of rail tracks that has recognized advantages over conventional technologies currently available to the railroad industry. The feasibility study, the development and the manufacture of a prototype will prove the capability of the proposed inspection technique for in-track rail flaw detection..

Publications:

Research staff involved: M.CARTON, J. TCHOUFANG TCHUINDJANG

Partners: MSM (S. Cescotto) (University of Liège)

Related project: Convention COOP-CT_2004-507622

§ Open Access to the Belgian Nuclear higher Education Network FP6-Actions to promote and develop human resources and mobility

Description: As the Consortium BNEN, five Belgian universities (KULv, UCL, UG, ULg, VUB) have established in collaboration with the federal Belgian Nuclear Research Center, a common Belgian Interuniversity Programme of the 3rd cycle, a "Master of Science in Nuclear Engineering". The aim of this project is to use the experience of the Consortium BNEN for the realization of a common "European Programme in Nuclear Engineering".

The objective of the BNEN project is to provide commonly accepted evaluation methodologies especially adapted for the assessment of education programmes; also the conclusions of an external evaluation of the BNEN scheme by EU-25 stakeholders in combination with a self assessment of the scheme, both based on the afore-mentioned evaluation methodologies. Another goal is to obtain recommendations and suggestions how the BNEN scheme and experience can be used for the creation of the common "European Nuclear Education Programme", and in extension how the scheme can be useful for the set-up of European education programmes in general. Finally, it should get points of particular interest that are of importance to stakeholders of the new member countries and to women, and that therefore need to be integrated into the common "European Nuclear Education Programme".

At the end the BNEN project will have contributed to the mobility of the European scientists and the creation of the European Area of Higher Education, to the integration of the candidate countries into the European Research Area and thus to the enlargement of Europe and also to the reinforcement of the place and role of women in science.

Publications:

Research staff involved:M.CARTON, M. HERMAN

Partners: ULg, UCL, RUG, VUB, KUL, SCK-CEN

Related project: Convention FP6-012564-BNEN