Solid-state phase equilibria in the Mg corner of the Mg-Gd-Sm phase diagram

The solid-state phase equilibria in the Mg corner of the Mg-Gd-Sm phase diagram were investigated by optical and scanning electron microscopy, X-ray diffraction and electrical resistivity measurements. The experiments showed that in the Mg corner of the system there are only three solid phases in equilibrium: the Mg solid solution and the two Mg-richest compounds of the adjoining binary systems. Each of the binary compounds take into solution significant quantities of the second rare-earth metal. Gd and Sm mutually reduce their solubility in the Mg solid solution. Isothermal sections of the phase diagram at 500 and 300 degrees C are presented.