Oxidation behavior of Atomized Fe40Al Intermetallics Doped with Boron and Reinforced with Alumina Fibers

摘要

Isothermal oxidation resistance of Fe40 (at. percent) Al-based atomized and deposited intermetallic alloys has been evaluated. The alloys included Fe40Al, Fe40Al + 0.1B, and Fe40Al + 0.1B + 10Al_2O_3 at 800, 900, 1000, and 1100 deg C. The tests lasted approximately 100 h, although in most cases there was scale spalling. At 800 and 900 deg C, the Fe40Al + 0.1B alloy had the lowest weight gain, whereas the Fe40Al alloy had the highest weight gain at 800 deg C (0.10 mg/cm~2) and the Fe40Al + 0.1B + 10Al_2O_3 alloy was the least oxidation resistant at 900 deg C with 0.20 mg/cm~2. At 1000 deg C, the Fe40Al + 0.1B alloy showed the highest weight gain with 0.12 mg/cm~2 and the Fe40A1 alloy the lowest At 1100 deg C, again, as at 900 deg C, 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.