Indentation creep studies of iron aluminide intermetallic alloy

Indentation creep behaviour of iron aluminide intermetallic (Fe-28Al-3Cr) was studied in the temperature range of 843-963 K. The hardness and the plasticity parameter were also calculated from room temperature to 1273 K. The variation of hardness with time showed that the stress exponent (n) was weakly dependent on temperature. Thermal activation parameter-activation area and energy were also calculated to identify the creep mechanism. The activation energy for high temperature creep was found to be in good agreement with that for self-diffusion of pure iron and in excellent agreement with previous studies. These values of n, activation area and activation energy were found to be consistent with dislocation climb as the rate controlling creep mechanism. Conventional creep curves were also derived from hardness values.