Abstract:

The phase constitution and microstructural characteristics in the as-cast and extruded Mg-Zn-Zr-RE system alloys have been studied. In the as-cast alloys, except for α-Mg matrix, there are Z ph-ase（Mg3RE2Zn3）and W phase（Mg3RE2Zn3） which are distributed along grain boundaries and Zn2Zr3 phase and ZnZr2 phase which precipitated in the matrix. In the extruded alloys, the dispersion-strengthening phase MgZn（phase）was precipitated both in the matrix and along the sub-grain boundaries in addition to the phases mentioned above.

Key words: magnesium alloys, rare earth, microstructures