Invar Properties of the Interstitial Carbides of Nd₂Fe₁₇
High-temperature x-ray diffraction experiments from 50 °C to 400 °C have been carried out to measure the thermal variations of the lattice parameters of Nd2Fe17Cx (x = 0.5, 1.0), which has the rhombohedral structure of the Th2Zn17 type, space group R3-m. the interstitial carbides Nd2Fe17Cx, together with their parent Nd2Fe17, exhibit Invar-like thermal expansion anomalies below their Curie temperatures, Tc. Although the introduction of carbon into Nd2Fe17 leads to lattice expansion and enhancement of Tc, the observed positive spontaneous magnetostriction of the carbides is comparable with that of Nd2Fe17. It is proposed that such a spontaneous magnetostriction can be ascribed to the occurrence of some short Fe-Fe distances and the strong distance dependence of the positive and negative interactions.
X. D. Zhang et al., "Invar Properties of the Interstitial Carbides of Nd₂Fe₁₇," IEEE Transactions on Magnetics, Institute of Electrical and Electronics Engineers (IEEE), Jan 1995.
The definitive version is available at http://dx.doi.org/10.1109/20.489704
Article - Journal
© 1995 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.