A random bond Ising model applied to the magnetic properties of FeXMn0.6-XAl0.4 disordered alloys

An Ising Hamiltonian, which includes diluted and random bonds, and the Mean Field Renormalization Group (MFRG) technique were used to obtain a theoret ical phase diagram as a function of the antiferromagnetic sites concentrati on for the FexMn0.6-xAl0.4 system. A probability distribution was proposed in order to simulate the diluted and random bonds of the system. The compet itive parameters and the exchange constants were fitted in such way that th e calculated magnetic phase diagram was in excellent agreement with the exp erimental phase diagram obtained by magnetic susceptibility for the FexMn0. 6-xAl0.4 alloy system. This model as well as the experimental results, prop ose several magnetic phases: antiferromagnetic, spin-glass, reentrant spin- glass, ferromagnetic and paramagnetic.