Effects of Laves phase particles on recovery and recrystallization behaviors of Nb-containing FeCrAl alloys

The microstructures and mechanical properties of deformed and annealed Nb-containing FeCrAI alloys were investigated. Fine dispersion of Fe2Nb-type Laves phase particles was observed in the bcc-Fe matrix after applying a thermomechanical treatment, especially along grain/subgrain boundaries, which effectively stabilized the recovered and recrystallized microstructures compared with the Nb-free FeCrAI alloy. The stability of recovered areas increased with Nb content up to 1 wt%. The recrystallized grain structure in Nb-containing FeCrAI alloys consisted of elongated grains along the rolling direction with a weak texture when annealed below 1100 degrees C. An abnormal relationship between recrystallized grain size and annealing temperature was found. Microstructural inhomogeneity in the deformed and annealed states was explained based on the Taylor factor. Annealed Nb-containing FeCrAI alloys showed a good combination of strength and ductility, which is desirable for their application as fuel cladding in light water reactors. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.