Structural and magnetic study of mechanically alloyed Fe30Cr70 by neutron thermo-diffractometry and magnetization measurements

Abstract : The temperature dependence of magnetization together with neutron powder thermo-diffraction show that nominal ball milled Fe30Cr70 for 110 h is formed of two mixed phases (Fe20Cr80 + Fe), both of them with body centered cubic crystal structure and very close values for the lattice parameter (not, vert, similar2.87 Å). On heating above 900 K, the system exhibits an irreversible structural transformation, giving rise to the homogenization of the material, and then recovering the well-defined starting composition Fe30Cr70. Subsequent heating-cooling neutron thermo-diffraction cycles do not show any additional transformation, thus explaining the overlapping M(T) curves after the first heating.