Interstitial modification of rare-earth intermetallics

Authors

Ralph Skomski, University of Nebraska-LincolnFollow
S. Murray, Trinity College, Dublin, Ireland
S. Brennan, Trinity College, Dublin, Ireland
J.M.D. Coey, Trinity College, Dublin, Ireland

Date of this Version

May 1993

Comments

Published by Am Inst of Physics. J. Appl. Phys. 73 (1993) 6940-6942. Copyright 1993. Permission to use. http://www.aip.org/.

Abstract

Interstitial modification of R₂Fe₁₇Z_x is studied with R=Y, Sm, and Z=N, C, B, Si, and S. Equilibrium interstitial concentrations are calculated using a lattice gas model. For gas-solid reaction a low solubility is obtained at high temperatures, whereas a solid-solid reaction is predicted to yield R₂Fe₁₇Z_1.5 in the high-temperature limit. Theoretical results are compared with data on Sm₂Fe₁₇C_x produced by solid-solid reaction at 500 °C. Volume expansions up to 4.8% were obtained, which corresponds to x≈2. The concentrations of interstitial boron and silicon are much lower.