Influence of Volume Fraction of Long-Period Stacking Ordered Structure Phase on the Deformation Processes during Cyclic Deformation of Mg-Y-Zn Alloys

Deformation mechanisms in extruded Mg-Y-Zn alloys with different volume fractions of the long-period stacking ordered (LPSO) structure have been investigated during cyclic loading, i.e., compression followed by unloading and reverse tensile loading. Electron backscattered diffraction (EBSD) and in situ neutron diffraction (ND) techniques are used to determine strain path dependence of the deformation mechanisms. The twinning-detwinning mechanism operated in the alpha-Mg phase is of key importance for the subsequent hardening behavior of alloys with complex microstructures, consisting of alpha-Mg and LPSO phases. Besides the detailed analysis of the lattice strain development as a function of the applied stress, the dislocation density evolution in particular alloys is determined.

Automated summary

Deformation mechanisms in extruded Mg-Y-Zn alloys with different volume fractions of the long-period stacking ordered (LPSO) structure were investigated using electron backscattered diffraction (EBSD) and in situ neutron diffraction (ND) techniques. The twinning-detwinning mechanism in the alpha-Mg phase is crucial for the subsequent hardening behavior of alloys with complex microstructures, and the lattice strain development and dislocation density evolution were analyzed in detail in specific alloys.