Effects of multi-scale precipitated phases on the toughness of FeCrAl alloy investigated by varying cooling mode and RE doping

In order to clarify the factors affecting the toughness of FeCrAl alloy, a systematic investigation on the correlation between microstructure and mechanical properties of hot-rolled 0Cr21Al6 sheet was performed through regulating cooling rate and rare earth (RE) element added in the alloy. It is worked out that a slower cooling rate results in the increase of brittleness for the alloy mainly due to nanoscale α' precipitates, while RE element promotes recrystallization and hinders the precipitation of sub-micron (Ti,Nb)P, which is beneficial to improving the toughness of alloy. These findings offer a valuable technical guidance for enhancing the toughness of FeCrAl alloy.