Microstructure and room temperature strength of Fe-40Al containing nanocrystalline oxide particles Original Research Article

The microstructure and room temperature strength of a mechanically alloyed ODS FeAl alloy are examined in a large number of differently processed and heat-treated materials and the strengthening contributions due to nanocrystalline oxide particles, to fine grain size, and to matrix effects are analysed. Submicron grain materials with small oxide particles show significant hardening due to the fine particles and a similar, significant hardening due to the fine grain size. The texture created during processing influences strengthening by determining the barrier efficiency of the lower-angle or higher-angle grain boundaries present, and thus modifies the Hall–Petch slope describing grain-size strengthening.