The influence of plastic deformation on the kinetic of precipitation and the morphology of precipitates in an Al-Zn 4.4 % at. studied by T.E.P. and SAXS is reported. Some results can be pointed out ; after a given amount plastic deformation at room temperature by tensile strength:
i - the precipitates have a flat shape (instead of the spherical or ellipsoidal shape usualy observed in this alloys.
ii - the precipitate volume fraction is a function of strain (ε) and strain rate (ė). For a given ė, the higher precipitate volume fraction is obtained with the higher ε. For a given ε, the lower ė the higher the volume fraction of precipitates.
iii - the scattering intensities at small angle for three orientations of the sample (α =0,45°, 90° where α is the angle between the axis of tensile and the scattering vector- are different. A calculation for an anisotropic orientation of flat discs shows that precipitates have a preferential texture. The orientation is about 50° from the tensile axis.