The effect of Friction Stir Processing (FSP) on the mechanical properties of a Sc, Zr modified 2024 aluminium alloy was investigated in the present paper. The room temperature tensile properties of the material were obtained in longitudinal direction respect to the processing one and compared with those of the unstirred material and unmodified alloy. Tensile tests were also performed at higher temperatures and different strain rates in the nugget zone. The superplastic properties of the recrystallized material were evaluated and the differences with the parent material as a function of the strong grain refinement due to the Friction Stir Process were put in evidence. The high temperature behavior of the material was studied, in longitudinal direction, by means of tensile tests in the temperature and strain rate ranges of 450-525 degrees C and 10(-1)-10(-3) s(-1) respectively. (c) 2006 Springer Science + Business Media, Inc.