Domain structures of ultrafine grained ferromagnets achieved by severe plastic deformation or melt quenching.
Lorentz electron microscopy was used to analyse the domain structure in some ferromagnets having an ultrafine grained structure produced by high pressure torsion (pure Ni, Fe, Co, Mn(55.5)Al(45.5) C(0.5)) and by melt quenching (Fe(83)Nd(13)B(4)). For low anisotropy ferromagnets (Ni, Fe, Co), it has been established that the domain structure does not depend strongly on grain size. In high anisotropy ferromagnets alloy (Mn(55.5)Al(45.5) C(0.5) and Fe(83)Nd(13)B(4)), grain refinement causes changes in the domain structure configuration and affects the magnetization mechanism.
Korznikova
G F
GF
Institute for Metal Superplasticity Problems of RAS, Khalturin str. 39, 450001 Ufa, Russia. korznikova@anrb.ru