Invar properties of the interstitial carbides of Nd/sub 2/Fe/sub 17/

High-temperature X-ray diffraction experiments from 50/spl deg/C to 400/spl deg/C have been carried out to measure the thermal variations of the lattice parameters of Nd/sub 2/Fe/sub 17/C/sub x/ (x=0.5, 1.0), which has the rhombohedral structure of the Th/sub 2/Zn/sub 17/ type, space group R.