Fe1-xHfx (X=0.33, 0.50) thin multilayered films were annealed in a high vacuum at temperatures of 350 and 500 degreesC, for 1 and 3 h. The solid state reacted films were characterized by Rutherford backscattering spectroscopy, magnetization and Mossbauer spectroscopy. The results revealed the formation of an amorphous phase and a metastably extended Hf(Fe) solid solution, for both film compositions. The crystalline phase Fe2Hf and a disordered magnetic phase were also identified in the annealed samples, iron-rich and equiatomic, respectively. The products obtained by SSR in the Fe-Hf was compared with those previously obtained in the Fe-Zr system. A schematic diagram of the Gibbs free energy vs. composition was proposed in order to explain the experimental results. (C) 2003 Elsevier B.V. All rights reserved.