Modifikace strukturních a mechanických charakteristik slitiny Al při ECAP procesu

Abstract

Materials processed by methods of severe plastic deformation (SPD) are characteristic for their ultrafinegrained structure and excellent mechanical properties. The thesis is focused on the deformation behavior of Al-Cu alloy processed by equal channel angular pressing (ECAP) (routes BC and C) up to 5 passes. ECAP was done using a 90° die and with a curvature extending over an angle of Ψ=20°. The ultimate tensile strength (UTS), micro hardness and microstructure were studied for both deformation routes. For structure changes evaluation was chosen optical microscopy as well as SEM and TEM. With the increasing number of passes there was observed significant improvement in UTS and hardness. Quite surprising results were obtained from mutual comparison of both routes. Regarding microstructure refining it is possible to note that after fourth pass (BC) was more efficient process. Average grain size after BC route was 200 nm.