The magnetization and magnetostriction curves of tetragonal TbFe11Ti s
ingle crystal along the main crystallographic directions in static mag
netic fields up to 7 T and the temperature interval 4.2-340 K have bee
n measured. On the basis of these data, the temperature dependences of
the anisotropy constant K-4(4)(T), magnetostriction constant lambda(2
)(alpha 2)(T) and the value of the f-d exchange parameter xi(0) were d
etermined and compared with theoretical results derived from the singl
e-ion anisotropy mechanism for the Tb sublattice.