Slip Line Kinetics during Deformation of Cu–Al Single and Polycrystals

Abstract

The formation and structure of slip lines, recorded by video during tensile deformation and supplemented by EM replica after deformation at room temperature is compared for Cu-5, 10, and 15 at% Al single crystals and polycrystals. Both show the same fine structure of slip lines in the slip bands and localization of slip increasing with solute concentration. In the first, stages of deformation, the active slip bands in single crystals are concentrated in a Luders band front propagating along the crystal length, while in the polycrystals (typical grain size up to 100 μm) the grains are activated at random along the crystal length starting with the largest grains and with preferred slip systems (mostly only 2 or 3) mostly according to Schmid's law, but activated with different succession in parts of the grains. The kinetics of single slip bands is similar in both poly- and single crystals, indicating similar elementary processes for their activation and development.