Neutron diffraction and extended X-ray absorption fine structure studies of Pr/sub 3/(Fe/sub 1-x/Co/sub x/)/sub 27.5/Ti/sub 1.5/ permanent magnet compounds

Neutron diffraction (ND) and extended X-ray absorption fine structure (EXAFS) measurements were carried out to determine the long-range and short-range structural properties of Co-substituted Pr/sub 3/Fe/sub 1-x/Co/sub x/Ti/sub 1.5/ compounds. ND refinement analysis indicates Ti atoms occupy the 4g and 4i Fe sites and Co atoms occupy, without preference, those Fe sites not shared with the Ti atoms. EXAFS measurements show the local environment of the Pr experiences increasing static disorder with the introduction of Co, and its coordination sphere contracts in the vicinity of those Co near neighbors. The Fe local environment remains unaffected with the introduction of Co suggesting that substitution in excess of 40% can be achieved in this structure.