Substitution Effect of Fe Sites in Nd2Fe14B

In order to investigate the magnetic contributions of each iron site of Nd
2
Fe
14
B, the magnetic properties of Nd
2
(Fe
1-x
M
x
)
14
B (M=Al, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Pt) were measured, and the preferential occupation of Fe sites by M atoms was studied by Mossbauer spectroscopy. The Mossbauer spectra were analyzed by a method of our own devising, which takes into account the effect of the environment and the degree of preference of each Fe site. These analyses revealed that the Curie temperature T
c
increases with increases in the lattice parameter c accompanying preferential substitution of M atoms at the k
1
and j
1
sites, but decreases when j
2
site is preferentially occupied by M atoms. It seems that the ferromagnetic interaction between Fe planes increases with the lattice expansion and decreases as j
2
site is occupied by M atoms. On the other hand, T
s
decreases when there is preferential substitution at c site. This fact suggests that T
s
is related to the interaction between Fe and Nd atoms.