Investigation of magnesium-copper eutectic alloys with high thermal conductivity as a new PCM for latent heat thermal energy storage at intermediate-high temperature

The aim of this paper is to explore Cu-Mg metallic alloys with high thermal conductivity as intermediate/high-temperature Phase Change Materials (PCMs) for latent heat storage at Concentrated Solar Power plants (CSP). Two binary eutectic alloys Mg84Cu16 and Mg59Cu41 (at.%) were investigated in terms of their structural, thermophysical and corrosion performance. In particular, homogeneity, eutectic composition, melting point, latent heat, specific heat, thermal diffusivity, thermal conductivity and density were investigated. Additionally corrosion tests were performed with common constriction materials like SS304 and SS316. The obtained results make magnesium-copper alloys one of the most promising materials for thermal energy storage application due to the highest thermal conductivity reported so far in 400-550 degrees C temperature range and their good thermal stability.