Growth of Single Crystals and Low Temperature Oxidation Behaviors of MoSi2 and NbSi2

Abstract:

Article Preview

In this paper, single crystals, around 8mm in diameter, of MoSi2 and NbSi2 have been grown by optical heating floating zone method. X-ray analysis confirmed that the as-grown ingots were single phase and single crystalline material. Oxidation behavior of the poly-crystalline and single crystalline MoSi2 and NbSi2 were characterized by measuring their weight changes as a function of exposure time. For arc-melted poly-crystalline samples, MoSi2 and NbSi2 fully turned into white powders after 160 and 3hrs exposure at 773K and 1023K respectively, which is known as the “pesting” phenomenon. As a comparison, no pesting was found in the dense spark plasma sintered (SPS) poly-crystalline samples and single crystals. The weight change of single crystals during exposure is found to be much lower than that of the SPS sample, indicating grain boundary plays an important role in the low temperature oxidation behavior of these two silicides.

Info:

Periodical:

Materials Science Forum (Volumes 475-479)

Main Theme:

Edited by:

Z.Y. Zhong, H. Saka, T.H. Kim, E.A. Holm, Y.F. Han and X.S. Xie

Pages:

729-732

DOI:

10.4028/www.scientific.net/MSF.475-479.729

Citation:

F. Zhang et al., "Growth of Single Crystals and Low Temperature Oxidation Behaviors of MoSi2 and NbSi2", Materials Science Forum, Vols. 475-479, pp. 729-732, 2005

Online since:

January 2005

Export:

Price:

$35.00

In order to see related information, you need to Login.

In order to see related information, you need to Login.