Influence of GdCl3 addition on purifying effectiveness and properties of Mg-10Gd-3Y-0.5Zr alloy

In order to improve the purifying efficiency of RJ6 flux, 5% (mass fraction) GdCl3 was introduced into the flux for refining Mg-10Gd-3Y-0.5Zr (GW103K) alloy. The results show that the RJ6 flux containing 5% GdCl3 exhibits better adsorption ability to nonmetallic inclusions than the one without GdCl3. Moreover, the mechanical, corrosion properties and fluidity of the alloy refined with RJ6 flux and RJ6 flux containing 5% GdCl3 were investigated, respectively. It is found that these properties are improved to a certain degree due to the removal of nonmetallic inclusions in the alloy. Thermodynamic analysis and surface tension experiments indicate that the main reason can be ascribed to the decrease of the surface tension of the flux with 5% GdCl3, which promotes the combination of flux and nonmetallic inclusions.