Oxidation behaviour of Fe–40 at.-% Al intermetallics with Li or Cu additions at high temperature

Abstract

Fe-40 at.-% Al intermetallics with the addition of Li (1 and 3 at.-%) and Cu (3 and 5 at.-%) were produced using standard casting techniques. The oxidation behaviour was obtained using thermogravimetric analyses in an atmosphere of 99.99% oxygen at 800, 900, 1000, and 1100°C. The oxidation product layers on the top and cross-sectional views were characterised using SEM and energy-dispersive X-ray spectroscopy mapping. The different alumina phases can produce a double layer with different mechanical and chemical properties. The results showed that the addition of 1% Li assisted the activation of the oxide production at 1000 and 1100°C, while the rest of the third element additions slightly modified the oxidation resistance.

Evaluation of Corrosion of a Fe-40Al-2RE Intermetallic Alloy in NS4 Solution

“…Although these materials have excellent behavior in high temperature conditions, they could be adequate in aqueous condition applications because of the high corrosion resistance as the effect of passive layer formation. This growing of passive layer has been presented by the Fe-Al base intermetallics exposed in O 2 gas at temperature up to 1000 °C (9,10), and in SO 2 gas at temperatures from 650 to 750 °C (11,12) inclusive. In other hand, recent corrosion studies of the iron aluminides in aqueous solution with sulfur contents have showed good corrosion resistance (13), and could be considered for potential applications in the area of energy transformation.…”