Gd contents, mechanical and corrosion properties of Mg–10Gd–3Y–0.5Zr alloy purified by fluxes containing GdCl 3 additions

Abstract

The effects of GdCl 3 in flux on the loss of Gd, microstructure, mechanical and corrosion properties of Mg–10 wt.% Gd–3 wt.% Y–0.5 wt.% Zr (GW103K) alloy were investigated. The results indicate that the loss of Gd in the alloy decreased when the melts were refined by fluxes containing GdCl 3 additions. Thermodynamic analysis revealed that the decline of Gibbs free energy is the main reason, which slows down the reaction rate between MgCl 2 and Gd in melts. In as-cast condition, after treated with 5 wt.% GdCl 3 additions, tensile yield strength, ultimate tensile strength and elongation of the alloy could reach the peak value of 201.51 MPa, 154.68 MPa and 2.56% respectively. 5 wt.% NaCl aqueous solution immersion test shows that the corrosion rate of GW103K alloy decreased to 0.437 mg cm −2 d −1 after refined by JDMJ + 5 wt.% GdCl 3. However GdCl 3 additions have no effects on microstructure and fracture pattern of GW103K alloy.