Increasing the creep resistance of Fe-Ni-Al-Cr superalloys via Ti additions by optimizing the B2/L21 ratio in composite nano-precipitates

(Left) Dark-field TEM micrograph of Fe-Ni-Al-Cr-Mo FBB8 ferritic alloy modified with 2.5%Ti aged at 700 °C, showing B2 precipitates (green) and Ti-rich L21 sub-precipitates (red). (Right) Plots of the L21 volume fraction within B2/L21 precipitates and creep threshold stress as a function of Ti concentration in the FBB8 alloys.349