The influence of volume fractions of particles on enhanced plasticity of Al-Al4C3 composites

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).