Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “FeBO3”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

Processing FeB03 glass-ceramics in space

The possibility of preparing FeBO3 glass-ceramic in space is explored. A transparent glass-ceramic of FeBO3, due to its unique properties could be an excellent material for magneto-optic applications which currently utilize high price materials such as single crystals of Ga-YIG. The unique magneto-optic properties of FeBO3 were found to come from glass-ceramic but not from the glass form. It was anticipated and later confirmed that the FeBO3 glass-ceramics could not be prepared on earth. Phase separation and iron valence reduction, were identified as the two terrestrial manufacturing obstacles. Since the phase separation problem could be overcome by space processing, the preparation of FeBO3 glass-ceramic in space appears attractive.

Li, C. T.↗

Study of iron-borate materials systems processed in space

It was calculated that an FeBO3B2O3 glass-ceramic containing only 1 mole% FeBO3 would be equivalent for magnetooptic application to a YIG crystal of equal thickness. An Fe2O3B2O3 composition containing 2 mole% FeBO3 equivalent (98B) could be converted largely to a dense green, though opaque, FeBO3 glass-ceramic through suitable heat treatments. However, phase separation (and segregation) and Fe+3 reduction could not be entirely avoided with the various procedures that were employed. From light scattering calculations, it was estimated that about 100 A to allow 90% light transmission through a 1 cm thick sample. However, the actual FeBO3 crystallite sizes obtained in 98B were of the order of 1 micron or greater.

Neilson, G. F.↗