Abstract
Elongated single-magnetic-domain iron particles, 150 angstrom units in diameter, have been prepared with properties that definitely confirm the existence of a shape anisotropy effect on coercive force. This conclusion is based upon four observations: (1) Torque curve analysis shows the predominating anisotropy effect to be uniaxial. (2) With increasing particle elongation, the temperature coefficient of coercive force departs from the temperature coefficient of crystal anisotropy and approaches the temperature coefficient of saturation induction. (3) Coercive forces greater than 2000 oersteds for iron have been measured. (4) A direct correlation is observed between particle coercive force and elongation.
- Received 19 April 1955
DOI:https://doi.org/10.1103/PhysRev.100.1055
©1955 American Physical Society