A quasicrystalline phase, Q, with icosahedral symmetry was detected by X-ray diffraction and transmission electron microscopy in Al-3Cr-xFe (x = 0, 1 or 3 at%) alloys elaborated by hot extrusion of rapidly solidified powders. Chemical microanalysis showed the average composition of this phase to be 75 +/- 0.5% Al, 12 +/- 1%Cr, 12 +/- 1% Fe. Annealing treatments led to its transformation into the equilibrium phases Al13Cr2 and Al13Fe4, directly at high temperature, or through a metastable and unknown phase, X, at intermediate temperature. This transformation was followed by X-ray diffraction, calorimetry and in situ electron microscopy. The convergent-beam technique was used for characterization of the X phase.