PHASE-ANALYSIS BY X-RAY AND MOSSBAUER-SPECTROSCOPY OF MELT-SPUN AND SUBSEQUENTLY ANNEALED SM-(FE, CO OR NI)-TI

A phase analysis by X-ray and Mössbauer spectroscopy of melt-spun SmxFe92 - xTi8, Sm(Fe10 - xCox)11Ti, Sm(Fe10 - xNix)11Ti and Sm10.5 - xCoxV1.5 annealed at temperatures between 600 and 900 °C was undertaken. For samples annealed at temperatures below 800 °C, especially for SmxFe92 - xT8 with 8 ≤ x ≤ 15, the TbCu7 phase crystallized initially, being dominant for x = 10 and 15. For 6 ≤ x ≤ 8 the TbCu7 phase disappeared above 800 °C, the ThMn12 phase becoming dominant. For x ≥ 10 a cubic, as yet unidentified, phase which was paramagnetic at room temperature was present in increasing amounts. The Mössbauer spectroscopy study confirmed the results of the X-ray phase analysis and allowed us to characterize the average magnetic state of iron in the TbCu7 phase. The observed trends in the dependence of the average hyperfine fields in Sm(Fe10 - xMx)11Ti with M = Co and Ni could be explained in terms of changes in the Curie temperatures resulting from the substitution of cobalt or nickel for iron. © 1990.