Low temperature remanent magnetization of Fe-Ni alloy.

Magnetic properties of synthetic 29at%Ni-Fe alloy were investigated for the purpose of understanding magnetization process of some meteorites. It was found that a stable remanent magnetization is acquired by cooling the alloy at 77K under the influence of geomagnetic field. This new type of remanent magnetization seems to be due to martensitic transformation from fcc to bcc phase of the alloy during which the crystalline anisotropy becomes zero. Natural remanent magnetization of some meteorites may possibly be of this origin.