High Temperature Oxidation of Fe-3Si Alloy

摘要

The high temperature oxidation behavior of Fe-3Si alloy was studied in oxygen for 0.3 ～ 18 ks at 873 ～1273 K, by mass gain measurements, X-ray diffraction (XRD), scanning electron microscopy (SEM), optical microscopy and electron probe microanalysis (EPMA). Mass gain of the alloy increased with increasing time and temperature of oxidation. Oxide nodules were formed on the alloy after oxidation at more than 973 K. After oxidation at 1273 K, the number of oxide nodules increased with increasing oxidation time, and these nodules for 0.3, 1.8, 7.2 and 18 ks were 20, 120, 250 and 350 μm in diameter, respectively. Oxide nodules consisted of the outer scale (Fe_2O_3, Fe_3O_4) and the inner scale (Fe_2SiO_4, SiO_2). Subscale was observed at the inner scale/substrate for 0.3 and 1.8 ks, however, the subscale disappeared after 7.2 ks oxidation at 1273 K.