Deformation of Al–Zn–Mg–Cu composite samples under nonstationary thermomechanical conditions

Abstract

The paper studies the technology of deformation and heat treatment of an aluminum-matrix composite material under nonstationary conditions, which is upsetting with gradual heating to near-solidus temperatures under mild loading conditions. The composite material is based on the V95 aluminum alloy discretely reinforced with 10% of SiC particles. The purpose of the study is to compare the deformation behavior of the samples and analyze their microstructure under different conditions of thermal deformation processing. The structure of the material is studied by optical and electron scanning microscopies. The paper discloses the behavior of the rate of relative strain as dependent on temperature, as well as the features of structure formation in an aluminum-matrix composite depending on the heating conditions. The most pronounced differences are found in the central part of the samples closer to the deforming tool (flat dies). On the symmetry axis in the central region of the samples there are differences in the crystallographic orientations of the material textures. Microhardness values and their distribution on the section are obtained. For the sample with slow heating, there is no tendency for the increase of the microhardness values in the regions with high values of plastic strain, this being indicative of a more complete recrystallization process and lower dislocation density.