Abstract:The microstructure and the texture of extruded 6061 Al alloy processed by powder metallurgy (PM), using three different initial powder particle sizes, have been studied after torsion deformation at 300 • C at strain rate of 6 s −1 . The initial extruded microstructure of the three alloys consisted of elongated grains confining substructure with a typical 1 1 1 + 1 0 0 fiber texture. After torsion deformation, the torque ( ) as a function of the equivalent strain (ε eq ) showed softening and the microstructure exhibited a gradient across the section so that the inner and outer zones contained sheared-elongated and small-equiaxed subgrains, respectively. It was observed that the equivalent strain to failure for the material processed using powder particles size of less than 45 m was of about ε eq ∼ 12, compared to ε eq ∼ 1 for material processed using powder particles size of less than 25 m. The microstructural changes during hot torsion deformation of PM 6061 Al alloy should involve continuous dynamic processes.