Accession Number : AD0776824

Title :   The Growth of Crystals of Rare Earth-Cobalt 1:5 Compounds.

Descriptive Note : Final technical rept. 1 Apr 70-31 May 72,


Personal Author(s) : Austin,Alfred E. ; Miller,James F.

Report Date : JUL 1972

Pagination or Media Count : 66

Abstract : Techniques were developed for the growth of single crystals of SmCo5, NdCo5, Sm(1-x)Nd(x)Co5 and PrCo5. The preferred method was by slow Bridgman drop of rare-earth rich melts in pyrolytic boron nitride containers. Large crystals, up to 2 x 1.5 x 1.5 cm of SmCo5 were grown with low oxygen content of 50 to 75 ppm. X-ray topography and rocking crystal curves were used for characterization of single crystals of SmCo5. The main crystal imperfections were low angle (0.5 to 1.5 degrees) boundaries and dislocations. It was shown that the low-angle boundaries pin magnetic domain walls with about 500 oersted magnetic fields needed for moving the domain walls. The vapor phase reduction of samarium tricyclopentadienyl and cobalt biscyclopentadienyl was demonstrated to yield Sm, Co, and Sm2Co17 at 500C. (Author)

Descriptors :   *Rare earth compounds, *Cobalt alloys, *Crystal growth, Single crystals, Crystal defects, Magnetic domains, Intermetallic compounds, Samarium, Neodymium, Praseodymium, Permanent magnets, Vapor deposition

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE