The research activities on metallic materials
The research activities of IMAP on metallic materials deal with engineering applications that require optimized combinations of structural and/or functional properties. This is particularly the case for the transport industry facing increasing demands on safety and sustainable development issues. Indeed, fuel consumption and gas emissions have to be drastically reduced through structure lightweighting while increasing safety and comfort devices.
A continuous need for metallic materials with improved mechanical properties requires
- The identification of the physical mechanisms responsible at the micro- and nanoscopic scales for the strength, deformation, and fracture resistance;
- The definition and characterization of the microstructures responsible for these mechanisms;
- To design thermomechanical processing routes leading to these optimised microstructures.
Steels, aluminium and titanium alloys
The three largest families of engineering metallic materials, i.e. steels, aluminium and titanium alloys, are the topics of numerous research projects for more than 10 years. Particularly, the resistance and forming properties of newly designed high strength formable steels or titanium alloys are continuously enhanced by combining several strengthening mechanisms at different scales.
Several studies are devoted to process, characterise, model and control the microstructure of
- (i) new generation steels involving finely grained microstructures and/or mechanical twinning (TWIP) and / or stress-induced martensitic transformation (TRIP);
- (ii) newly designed β metastable titanium alloys (Ti-555, Ti-12Mo);
- (iii) new aluminium alloys presenting enhanced fracture strain or self-healing abilities.
On the other hand, the relationship between microstructure characteristics and resistance to damage and crack propagation of aluminium alloys for aerospace applications is characterised and modelled. These property-driven research topics are sustained by generic research projects on experimental characterisation of phase transformations and micromechanical behaviour and on microstructure-based modelling of plasticity and fracture.
The same research philosophy has been recently applied to the development of Heusler compounds for energy applications. More precisely, Fe-based compounds are studied for low grade heat harvesting through the thermoelectric or thermomagnetic effects.
Research funding comes from both fundamental and applied public research sources, as well as directly from industry.