Development of Twin Fractions and Microstresses of the Hot Extruded Magnesium Alloy AZ31 under Cyclic Loading Conditions
For investigating the twinning and detwinning behaviour under cyclic loading conditions in-situ stress measurements with different applied strain amplitudes were performed at the beamline 7T-MPW at BESSY II. Intensity measurements of the (10-10), (11-20) and (0002) reflections served for the determination of the twinned volume fraction. The measurements of the (hkil) dependent strains and stresses gave information on the load partitioning between different grain orientations. The intensity measurements performed in the compression regime showed that the evolution of the (0002) reflection intensity depends on the strain amplitude. For strain amplitudes ≥ 0.75 % an increase in intensity is observed whereas for smaller strain amplitudes the (0002) intensity decreases with increasing cycle numbers. In the tensile regime an increase in the (0002) reflection intensity is found for the whole range of applied strain amplitudes.
T. Chandra, N. Wanderka, W. Reimers , M. Ionescu
M. Huppmann and W. Reimers, "Development of Twin Fractions and Microstresses of the Hot Extruded Magnesium Alloy AZ31 under Cyclic Loading Conditions", Materials Science Forum, Vols. 638-642, pp. 2411-2416, 2010