ENTHALPIES OF B2 ANTIFERRO-FERROMAGNETIC AND METASTABLE FCC-B2 TRANSFORMATIONS IN FERH

Ferromagnetic ordered bcc-B2 FeRh becomes antiferromagnetic below abou t 400 K. It also transforms to a paramagnetic fee phase after heavy de formation. We report for the first time transformation enthalpies of F eRh for the metastable fcc --> ordered bcc (B2) and antiferro --> ferr omagnetic transitions. Delta H-fcc-B2 approximate to 8 kJ g.atom(-1) n ear 600 K. Delta H-antiferro-ferro approximate to 450 J g.atom(-1) cor responding to Delta S-antiferro-ferro approximate to 1.2 J g.atom(-1) K-1 as compared to Delta S-antiferro-ferro approximate to 1.4 J g. ato m(-1) K-1 obtained from magnetic and Delta S-antiferro-ferro approxima te to 1.2 J g atom(-1) from pressure effects. Copyright (C) 1996 Elsev ier Science Ltd