Study on the effect of glass on the properties of Na2CO3-K2CO3 eutectic salt/MgO composite as phase change thermal storage materials

The salt/ceramic phase change materials (PCMs) have a good thermal storage performance and high application temperature. In this paper, we studied the effect of glass as additive on the mechanical properties, thermal storage, and morphology of the Na2CO3-K2CO3 eutectic salt/MgO composite PCMs. The results show that glass can effectively improve the compressive strength of MgO matrix material. When the mass ratio of glass and MgO is 7:3, the compressive strength of the composite body can be up to 104.3 MPa. When the mass ratio of Na2CO3-K2CO3 eutectic salt, MgO, and glass is 55:25:20, the composite PCM body has a good stable form, and its total heat storage is 788 J/g, which increased by 6.7% compared with the total heat storage of composite PCMs without glass in the range of 150°C~750°C. When the mass ratio of Na2CO3-K2CO3 eutectic salt, MgO, and glass is 55:15:30, the composite PCM body cannot maintain stable form.