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The fatigue crack behavior of metals is strongly governed by the grain size variation. As for tensile strength, the fatigue limit increases with decreasing grain size up to the microcrystalline regime. A different behavior in terms of mechanical properties has been demonstrated in many papers for metals with ultra fine and nanocrystalline (< 100 nm) grain size, in particular for the yield stress value and fatigue crack initiation and growth. The fatigue crack propagation of pure titanium, pure nichel and copper with ultra fine grain structure has been analyzed in the present paper. In particular, the fatigue crack initiation phase and growth of these materials in the form of thin plates was studied over a broad range of stress levels and life cycles.