Abstract
Deformation process of the Al-Al₄C₃ composites with different volume fraction of Al₄C₃ phase was tested at different temperatures and different strain rates. As shown, at temperatures 673–723 K and the highest strain rate applied 10^-1 s^-1, a significant increase of ductility was observed. According to the results of transmission electron microscopy analysis (TEM), this behaviour is supposed to be the result of dynamic grain polygonization, grain slip and rotation, partial recrystallization and dislocation creep in the tested system, known as the strain induced dynamic recovery. Increase of the volume fraction of second phase in the investigated composite changed the deformation mechanism (from more grain boundary sliding to predominantly grain rotation).

Key words
composite material, strain rate, TEM analysis, superplasticity

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