Crystallography of directionally solidified magnesium alloy AZ91

Abstract

The crystallographic direction of growth in directionally solidified magnesium alloy AZ91 has been studied by TEM and EBSP techniques in SEM. The main direction of growth is found to be$\left\langle {11\bar 20} \right\rangle$. The dendrites have sixfold symmetry around the main direction, with secondary arms lying along the traces of the (0001),$\left( {1\bar 101} \right)$, and$\left( {\bar 1101} \right)$-planes, respectively. The secondary arms lying in the basal plane are crystallographically of the same type as the main direction:$\left\langle {\bar 12\bar 10} \right\rangle$ and$\left\langle {2\bar 1\bar 10} \right\rangle$.