Microstructure evolution of Mg-11Gd-4.5Y-1Nd-1.5Zn-0.5Zr (wt%) alloy during deformation and its effect on strengthening

Microstructure and texture evolutions during tensile and compression deformation of an as-extruded Mg-11Gd-4.5Y-1Nd-1.5Zn-0.5Zr (wt%) alloy have been investigated using in-situ synchrotron radiation diffraction and subsequent microscopy. The alloy consists of 〈101¯0〉 fiber texture, {112¯0}[0001] and {112¯0}〈101¯0〉 texture components prior to deformation. The texture evolves from [0001] to 〈101¯0〉 in tension, but from 〈101¯0〉 to [0001] in compression. The evolution of texture is attributed to the activity of the tensile twinning and non-basal 〈a〉 type slip. The tendency of texture evolution depends on the favorable texture component for the activation of above deformation modes. The grain refinement, Mg5(Gd, Y, Nd) and LPSO phases, and the texture contribute to the improvement in strength.