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Microstructural modifications and their effect on tensile properties in an Fe-7 wt.% Al alloy by additions of 0.5% TiB2, 0.5% ZrB2 or both has been studied. Alloys are examined in the as-cast as well as in the hot-rolled and annealed conditions. Solidification structure of the Vacuum Arc Remelted pancake ingots was columnar dendritic. Further, boride modified alloys are found to have finer grains in as-cast as well as in hot-rolled and annealed conditions. In the annealed condition, boride containing alloys were found to have superior tensile yield strength, ductility and strain hardening behaviour. These property improvements are attributed to boride aided grain refinement during casting as well as during thermo-mechanical processing of the steels.

International audience; For the first time, the piezomagnetic behavior of polycrystalline Fe-Al-B alloys is accessed. Piezomagnetic factors of up to 4.0 kA.m −1 /MPa were reached for an interval of applied compressive stresses between 0 to-140 MPa. The experimental results together with a powerfull multiscale and bipha-sic modeling allowed the general understanding of the magnetostrictive and piezomagnetic behaviors of these materials. The magnetic and mechanical localizations as well as homogeneous stresses were considered in the modeling and are associated to the intrinsic presence of the Fe 2 B phase. The interplay of the magnetocrystalline anisotropy, initial susceptibility, saturation magnetostriction and texture were quantified by the model and compared to the experimental results. An improvement of the piezomagnetic factor to 15 kA.m −1 /MPa is predicted, for an alloy containing 20% of aluminum, by getting an adequate texture near < 100 > directions.