On nanoparticles of the ferromagnetic Cu2MnAl phase in Cu–Al–Mn shape memory alloys

We investigate nanoparticles of the ferromagnetic Cu2MnAl phase which precipitate from a supersaturated paramagnetic Cu-Al-Mn solid solution. Changes of the magnetic properties of those particles during the martensitic transformation are caused by the internal stresses which arise due to the misfit between the lattices of the particles and the martensite. An increase of the magnetic anisotropy constant of the particles has been revealed. This increase can be attributed to the increase of the coherency stresses. The intensity of the coherency stresses has been evaluated on the basis of magnetic measurements.