Plastic deformation properties of the complex metallic alloy phase μ-Al-Mn

The macroscopic plastic deformation behaviour of high-quality single crystalline samples of the hexagonal complex metallic alloy μ-Al-Mn was investigated. We have performed uniaxial deformation experiments at a constant strain rate of 10−5 s−1 at temperatures between 700 and 875 °C and with a compression direction parallel to the c-axis of the crystal structure. The stress-strain curves show a pronounced yield-drop effect followed by a steady-state flow-stress regime. Stress-relaxation tests and temperature changes were performed in order to determine the thermodynamic activation parameters of the deformation process. First microstructural investigations of deformed samples were carried out by means of transmission electron microscopy. In the geometry applied, deformation takes place by two systems of dislocations, both moving by pure climb, which interact by an exchange of vacancies.