Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1630513 | Journal of University of Science and Technology Beijing, Mineral, Metallurgy, Material | 2007 | 4 Pages |
Abstract
The oxidation behavior of molybdenum disilicide (MoSi2) powders at 400, 500, and 600°C for 12 h in air were investigated by using X-ray diffraction (XRD) and transmission electron microscopic (TEM) techniques. Significant changes were observed in volume, mass, and color. Especially at 500°C, the volume expansion was found to be as high as 7-8 times, the color changed from black to yellow-white, and the mass gain was about 169.34% after 8 h, with SiO2 and MoO3 as main reaction products. The gains in volume and mass were less at 400 and 600°C compared with those at 500°C, probably due to the less reaction rate at 400°C and the formation of silica glass scale at 600°C, which would protect the matrix and restrain the diffusion of oxygen and molybdenum. Thus, the accelerated oxidation behavior of MoSi2 powder appeared at 500°C and the volume expansion was the sign of accelerated oxidation.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Peizhong Feng, Xuanhui Qu, Islam S. Humail, Xueli Du,