Meltrefreeze

Meltrefreeze is a term used in materials science to describe a reversible cycle in which a material repeatedly transitions between a melted (liquid) state and a refrozen (solid) state as ambient or applied temperatures cross the material’s melting point. The concept appears in discussions of phase-change materials (PCMs) and other systems that exploit latent heat for thermal management.

Mechanism and materials: The energy exchange arises from latent heat of fusion during melting and solidification. The efficiency and repeatability of meltrefreeze cycles depend on the material’s melting point, heat of fusion, thermal conductivity, and resistance to leakage or structural degradation. In practical implementations, encapsulated or composite PCMs—such as paraffin waxes, salt hydrates, or metal alloys—are used to contain the liquid phase and improve cycling stability. Nucleation, crystallization kinetics, impurities, and confinement geometry influence how reliably refreezing occurs and whether supercooling or phase separation develops.

Applications and challenges: Meltrefreeze cycles are of interest for thermal energy storage, enabling higher energy density in solar or waste-heat recovery systems, as well as for temperature regulation in buildings and electronics. Challenges include leakage of liquid phase, volume changes during phase transition, corrosion at containment interfaces, and material degradation over many cycles. Ongoing research seeks better encapsulation, improved cycle stability, and cost-effective PCM formulations.

See also: Phase-change material, latent heat storage, thermal energy storage, supercooling.