THE COEFFICIENT OF THERMAL EXPANSION OF FE3AL AND FeAl - TYPE IRON ALUMINIDES

The iron aluminides seem to be very perspective materials for use in high-temperature structural applications. They are promising materials for a possible replacement of high alloyed steels of P91 or P92 type. But it is very important to know the coefficient of thermal expansion (CTE) of iron aluminides for use as structural materials at high temperatures. It can also be determined phase transformations in the alloy from CTE measurement. In this paper there were studied the differences in CTE-curves between Fe3Al (D0(3) structure) and FeAl (B2 structure) type iron aluminides. It was investigated the coefficients of thermal expansion and phase structure of three samples in temperature range 440 -1200 degrees C.