Solid solution and precipitation strengthening effects in basal slip, extension twinning and pyramidal slip in Mg-Zn alloys

A high-throughput methodology is proposed, based on the combination of diffusion couples and advanced nanomechanical testing methods, to directly measure alloying effects critical resolved shear stress (CRSS) individual deformation modes in Mg alloys. The tested Mg-Zn alloys by assessing effects, up Zn contents 2 at.%, basal slip, extension twining pyramidal slip two metallurgical conditions: as-quenched, for which solute atoms remain homogenously dispersed solid solution; peak-aged, form rod-shape ? 1 ? (MgZn ) precipitates. combined approach including micromechanical testing, transmission Kikuchi diffraction, high-resolution electron microscopy was performed reveal corresponding mechanisms. It found that CRSS enhancement twinning MgZn precipitates considerably larger than effect solution, while strengthening similar both cases. As a result, anisotropy ratios high pure solution strengthened However, they are substantially reduced precipitation