Design of novel high strength ultrafine grain Al alloys via spinodal decomposition – SpinodalDesign

The need to reduce greenhouse gas emissions in transport - automobiles, aeronautics - makes it essential to develop light alloys with mechanical properties beyond those achieved by traditional processes. The objective of the SpinodalDesign project is to design such aluminum-based alloys, by combining a nanostructure of crystalline defects resulting from severe plastic deformation, and a nanostructure of distribution of chemical species obtained by spinodal decomposition and clustering. Successfully combining these hardening methods requires removing a certain number of scientific and technological obstacles, defining the axes of the project. First, a large landscape of alloy design will be explored by a combinatorial approach, based on materials with compositional gradient, subjected to severe deformation processes. For this purpose, a high throughput characterization approach coupled with thermodynamic calculations is proposed. Secondly, the evaluation of the interactions between the dynamics of phase transformations and the evolution of structural defects will make it possible to define the conditions for a synergy between these evolutions. Finally, the nanostructures obtained will be linked with the mechanical properties of elasticity limit and deformability, in order to guide their optimization.
The three teams involved, two of which having long-standing collaborations, will implement in a complementary manner advanced techniques for the development and characterization of nanostructured materials, with a particular effort on in-situ measurements to follow the dynamics of transformation. The alloys defined during the project, designed to specifically combine nanostructure of structural defects and chemical nanostructure, will be adapted to industrializable processes and will therefore allow the development of competitive and environmentally friendly transport solutions.