In-situ neutron diffraction study of the deformation mechanisms in solutionized Mg-Zn alloys

In-situ neutron diffraction experiments were carried out on solutionized and randomly textured Mg-Zn alloy castings with similar grain sizes but variation in Zn content from 1.7 to 6.6 wt %. The evolution in internal elastic strains and diffraction peak intensities with increasing load were analyzed. The macroscopic stress strain curve shows an increase in yield strength with an increase in zinc content. Neutron diffraction results indicate that the strength of basal slip, tension twinning and slip/compression twinning modes increases with increase in zinc content. However, the strength of prismatic slip appears to be unaffected by zinc content at lower concentrations and increases with zinc content only at higher concentrations. These results are discussed in light of prior work on the Mg-Zn system.