Solid solution strengthening in ternary B2 iron aluminides containing 3d transition elements

The room temperature yield strengths of extruded ternary iron aluminides with the composition Fe-45Al-5X-0.2B-0.1Zr (at%), where X stands for Ti, Cr, Mn, Fe, Co, Ni or Cu, were measured. With the exception of the Mn-containing alloy, all alloys showed solid solution strengthening following a 1 week/673 K vacancy removal anneal. Densities, lattice parameters and elastic constants were measured to determine vacancy concentrations as well as atomic size and modulus misfits. Although the strengthening could not be well described by established theories for dilute binary alloys, it could be reasonably well correlated with the magnitude of the atomic size misfit of the ternary alloying additions. Copyright (C) 1996 Elsevier Science Limited