Influence of atomic ordering and cerium doping on magnetostrictive Fe-Al alloys

•Heat treatment can boost the performance of magnetostrictive Fe-Al alloys.•Diffraction data reveal the correlation between atomic order and magnetostriction response.•Rapid cooling can prevent formation of long-range ordered domains in Fe-Al.•Fe-Al alloys display negligible solubility for cerium dopants. Magnetostrictive iron-aluminum alloys can be a low-cost, mechanically stable alternative to iron-gallium and rare earth-iron alloys. The magnetostrictive performance of polycrystalline Fe-Al (alfenol) with 13–24 at. % Al was investigated, studying the role of compositional variation and thermal history. It was found that rapid cooling enhances the magnetostrictive response, and peak magnetostriction was found in Fe78Al22 by high temperature annealing followed by quenching. Synchrotron diffraction enabled a direct correlation of magnetostrictive behavior and the transition from short-range order to long-range ordered cluster domains in the material which can be suppressed by rapid cooling. Following recent success of doping Fe-Ga with rare earth elements, we investigated the influence of Ce doping on improving magnetostriction and found that Fe-Al shows negligible solubility for cerium, inhibiting potential magnetostriction enhancement. Our results illustrate the complex interplay between phase stability, ordering, and optimized magnetostrictive response.