Oxidation behavior of atomized Fe40Al intermetallics doped with boron and reinforced with alumina fibers

Isothermal oxidation resistance of Fe40 (at.%) Al-based atomized and deposited intermetallic alloys has been evaluated. The alloys included Fe40Al, Fe40Al + 0.1B, and Fe40Al + 0.1B + 10Al(2)O(3) at 800, 900, 1000, and 1100 degreesC, The tests lasted approximately 100 h, although in most cases there was scale spalling. At 800 and 900 degreesC, the Fe40Al + 0.1B alloy had the lowest weight gain, whereas the Fe40Al alloy had the highest weight gain at 800 degreesC (0.10 mg/cm(2)) and the Fe40Al + 0.1B + 10Al(2)O(3) alloy was the least oxidation resistant at 900 degreesC with 0.20 mg/cm(2). At 1000 degreesC, the Fe40Al + 0.1B alloy showed the highest weight gain with 0.12 mg/cm(2) and the Fe40Al alloy the lo,vest. At 1100 degreesC, again, as at 900 degreesC, the Fe40Al alloy was the least resistant, whereas the Fe40Al + 0.1B alloy performed the best, but the three alloys exhibited a paralinear bahavior on the weight-gain curves, indicating the spalling, breaking down, and rehealing of the oxides. This spalling was related to voids formed at the metal-oxide interface.