Materials Science Forum, Vol.461-464, 455-462, 2004
High temperature properties of a new powder metallurgical FeCrAl alloy
Alumina forming FeCrAl alloys are at present the class of engineering metallic materials that shows the longest working lives in the temperature range >1100degreesC in oxidising environments. However, their mechanical properties at high temperatures are relatively poor and this prevents use of conventional FeCrAl alloys in highly stressed components. Powder metallurgy, in form of mechanical alloying and rapid solidification from melt has been shown to offer effective means to bypass this weakness. A recently introduced commercial alloy, Kanthal(R) APMT, an advanced example of application of rapid solidification to introduce dispersion strengthening in FeCrAl, was investigated and a selection of results is presented in the paper. The new alloy offers substantially increased hot strength and creep properties as compared to its relative Kanthal(R) APM, which is a result of increased amounts and different types of refractory inclusion and an addition of molybdenum. High temperature mechanical data are given in relation to other alloys and is discussed in relation to microstructural features. Oxidation properties up to 1200degreesC as well as application examples are presented and discussed.
Keywords:FeCrAl;dispersion strengthening;high temperature alloy;creep strength;oxidation properties;mechanical properties