Scientific activities, education, network

Team "Metallurgy and Functional Materials"

All of our research themes include: Numerical simulation of the microstructures and the proprieties, the Powder Metallurgy, Sintering mechanisms and studies, Fabrication of structural and functional materials, bulk and thin films, with adaptive properties, Synthesis and characterization of interfacial zones, Assembly (soldering or welding) of metallic materials in solid or liquid phase, the New ternary RE-TM-X (RE = Rare-Earth, TM = Transition Metal, X = p element or magnesium), the Hydrogen storage, hydrogenation, Metallic hydrides, Study, at the phase scale, of the genesis and of the microstructural evolution of intermetallics alloys, Study of the correlation between microstructural parameters and thermoelectric properties, the Magnetocaloric effect, magnetic cooling and  the Thermal stability of ultra fine microstructures.

Our scientific activities resulting from it:

Particule d'oxyde de cuivre
Particule d’oxyde de cuivre recouverte de nanofibres de CuO sur une fibre de carbone micrométrique / Oxide copper particles cover by CuO nanofibres sitting on top of a carbon micrometric fiber

 Conception of inorganic composite materials: Effect of the size (nanometric to micrometric), of the shape (fiber and particle), of the properties (physic and mechanic) and of the fabrication processes on the microstructural properties of metallic and ceramic composite materials.

Development of innovative sintering flash technique and understanding of the mechanism reaction: Role of the “apply field” parameter (electric (SPS) and microwave) on the sintering mechanism of metallic and ceramic composite materials.

Fabrication of innovative materials by non-conventional processes: Non-conventional processes like laser treatment, SPS, MS and PVD are used in non-equilibrium thermodynamic states. They can be used in order to obtained metastable microstructure in order to develop innovative materials with new functional properties.

New ternary intermetallics RE-TM-X (RE = Rare-Earth, TM = Transition metal, X = p element or magnesium): Synthesis, chemical and physical characterization of new ternary phases. Fields of interest: Energy (magnetocaloric effect, hydrogen storage, …), structural materials, …

Fusion d’intermétallique dans un four à haute fréquence / Fusion of intermetallics in a high frequency furnace

 Hydrogen storage, hydrogenation, intermetallic hydrides: Improvement of sorption properties of magnesium and BCC phases. Modulation of physical properties (structure, magnetism, superconductivity, transport, …) through hydrogen insertion in intermetallics containing rare-earth.

Magnetocaloric effect, magnetic cooling: Search of new phases with high magnetic density (based on rare-earth and transition metals) with ferromagnetic transition around room temperature.

Approche de développement de matériaux innovants / Approach to develop innovative materials :

Formation d’eutectique nanométrique par solidification rapide d’un alliage à base de cuivre (Cu-Mg) conférant à ce très bon conducteur électrique une haute limite d’élasticité / formation of nano-eutectic in Cu-Mg system from melt-spinning. The resulting material exhibits a remarkable balance between electrical conductivity and strength.

Mechanisms of microstructures formation in metallic alloys: Both the structural and functional properties depend strongly on microstructure features such size of phases, composition, dispersion, topology and 3D morphology. The latter result from phase transformations in solid state that depend from complex and coupled effects closely linked to the thermodynamic of the studied system as well as to thermal, composition and mechanic fields. The understanding of the involved mechanisms is addressed from an approach based on both experimental and modelling at the scale of phases. The main goal being to determine the relevant parameters that control the microstructure architecture and its time evolution.

Main networking and partnershiP

Programs:

  • International (MDA – USA): Fast Deposition of Diamond Films in Open Air for Thermal Management, Wear Resistance, and Corrosion Resistance
  • European (7 PCRD -large scale): EDEFU; Hydra
  • European (Euripides): SatPack
  • National (FUI): MC+
  • Regional: Direct report for electronic industry; ARCHIDIAMS ; SOLR2
  • ANR MAGCOOL (Magnetic refrigeration); Gracos (Programme Blanc Franco-Canadienne) ; Spiderman SIMI 8 ; PHIMS

Partners:

  • Nexans
  • Groupe Safran (Hispano Suiza, SES)
  • Alstom
  • Thales Aero Space
  • NovaPack SAS
  • Federal Mogul
  • Bertin Pharma, Serma Technologies et Schlumberger
  • Arcelor Mittal
  • A2C
  • ASTF
  • CEA Saclay, TECH/LITEN, Cadarache
  • Dassault-Aviation
  • Silimelt

Application examples:

- Thermal drains with adaptive properties: Cu and Al based / Micrometric reinforcement (C: Fiber or Particles)

- Conductive materials with enhance electrical performances: Cu based /Nanometric reinforcement (CNT)

- Generating electricity from thermoelectric effect in sustainable materials: Mg2(Si,Sn) and textured MnSi1.7 nanostructured solid solution

- A new high conductivity – high strength Cu-based alloy : Nano-eutectic Cu2Mg+Cu(Mg)

- New diffusion barriers in diamond coatings for aeronautic and spatial applications: TaN et ZrN nitrides

- (U,Pu)O2 combustible: Homogenizing mechanism with chromium / Densification behavior correlated with oxygen vapor pressure