High strength ultrafine eutectic Fe-Nb-Al composites with enhanced plasticity

An enhancement of plasticity in high strength ultrafine eutectic Fe-Nb composites has been accomplished by introducing heterogeneities in length-scale of the microstructure. Addition of Al acting as a stabilizer for the alpha-Fe phase in the Fe-Nb composites results in the formation of a larger volume fraction of primary alpha-Fe phase and an ultrafine eutectic structure with reduced lamellar spacing. As a result, Fe-Nb-Al composites exhibit a good combination of fracture strength and plasticity. Due to the presence of the solution hardened alpha-Fe phase, the Fe-Nb-Al composites exhibit significantly enhanced work hardening behavior at room temperature. (C) 2008 Elsevier Ltd. All rights reserved.