Heat resistance of Fe-Al intermetallics in the context of selected heat-resistant and hihg-temperature creep resistant steels

Results are hereby presented of heat-resistance tests of two Fe3Al and FeAl intermetallic phase-based alloys in the context of St41k-type boiler steel and 50H21G9N4 high-temperature creep resistant steel. It has been ascertained that heat resistance of the 50H21G9N4 steel and of the Fe3Al and FeAl intermetallic phase-based alloys significantly exceeds that of the boiler steel tested in the air atmosphere and the atmosphere of a flue gas with CO, CO2, SiO2 content alike. Improvement of these properties depends of exposure conditions. The largest differences have been observed when the tests were carried out in temperature 1023 K and in the flue gas atmosphere. The differences have been more and more noticeable as the exposition duration extended. A tendency has been also recorded of smaller mass decrements of the Fe3Al and FeAl intermetallic phase-based alloys as compared to the 50H21G9N4 steel.