In recent years, nanocrystalline materials have increasingly attracted interest, stemming from the fact that grains with sizes in the nanometer range lead to unusual properties. Mechanical alloying (MA) is one of the solid-state reaction techniques to produce non-equilibrium phases such as amorphous and nanocrystalline alloys. Fe-M-MT (M = Ni, Zr, Nb, MT = B, Si) alloys were produced in a planetary high-energy ball mill. The grain size decreases with the milling time and approach to a steady state (from 3 to 12 rim) after 80h milling. The calorimetric analysis shows the existence on heating of a recovery process beginning at low temperature and several processes associated to grain growth. The alloy with higher Ni content presents the lower thermal stability of the crystallization processes and a significant amorphous phase.