The back stresses in creep of a Fe-30Al-4Cr intermetallic alloy with addition of Zr

The creep behaviour of an Fe-Al-Zr alloy was examined at temperatures from 873 to 1073 K. Back stresses such as threshold stress and internal stress are evaluated. The activation volume of dislocation motion is estimated from measured values of creep rate and internal stress. Creep rate is determined to be inhibited by particles at 873 K and 923 K and is controlled by dislocation motion in a single-phase matrix at temperatures from 973 to 1073 K.