Life-time extension of alumina forming FeCrAl-RE alloys: influence of alloy thickness

Oxidation lifetimes of the FeCrAl-RE alloys at ultra high temperatures are governed ultimately by chemical failure of the protective alumina scale, of ten accelerated by prior mechanical failure resulting in scale cracking and spallation. Critical parameters involved in these failure modes are expect ed to be influenced by alloy thickness. Therefore, the effect of alloy thic kness upon the lifetime oxidation behaviour, in air, at 1,300 degrees C has been studied for three commercial FeCrAl-RE alloys, Kanthal AF, Kanthal AP M and PM2000, that have been fabricated by the three principal fabrication routes. As a result, these alloys have different creep properties, which al so could have a significant influence on oxidation behaviour.