High-field magnetostriction measurements on Fe14Nd2B magnets

Magnetostriction measurements have been made on aligned polycrystalline Fe 14 Nd 2 B magnets from two US manufacturers at applied fields up to 144 kOe at room temperature. The ordinary magnetostriction is comparable to that of iron (10 × 10 -6 ). The high field forced magnetostriction is positive for all orientations of the field and of the measured strain, strongly anisotropic, and similar in magnitude to normal ferromagnetic materials. The forced volume magnetostriction is 1.3 × 10 -9 Oe -1 with the field parallel to the alignment axis, and 2.1 × 10 -9 Oe -1 with the field perpendicular.