Computational design of light and strong high entropy alloys (HEA) Obtainment of an extremely high specific solid solution hardening

A multi-objective optimisation genetic algorithm combining solid solution hardening (SSH) and thermodynamic modelling (CALPHAD) with data mining is used to design high entropy alloys (HEAs). The approach searches for the best compromise between single-phase stability, SSH and density. Thousands of Pareto-optimal base-centred cubic (BCC) HEAs are designed. AlCrMnMoTi (at.%) is chosen for experimental validation. The alloy was cast and characterised. Its microstructure consists of large grains of a single disordered solid solution displaying a Vickers hardness of 6.45 GPa (658 HV) and a density below 5.5 g/cm; uniquely combining exceptional hardness with medium density.
Philippe Castany acknowledges the THEMIS platform of the University of Rennes for providing access to TEM facilities. The work of Franck Tancret at the University of Cambridge was funded by the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie grant agreement No. 656249: “Computer-Aided Design Of Revolutionary Superalloys” (CADORS). The present document reflects only the author's view; the European Union's Agency is not responsible for any use that may be made of the information it contains.info:eu-repo/grantAgreement/EC/H2020/656249