meltinu

Meltinu is a fictional material used in speculative fiction and worldbuilding. It is described as a phase-change substance capable of switching between solid and liquid states under relatively low energy input, allowing rapid modulation of heat and shape.

In many depictions, meltinu has a tunable melting range from near room temperature to a few hundred degrees Celsius. The solid form is crystalline or amorphous and stiff; the liquid form is viscous and highly moldable. The transition is cyclic and stable under ideal conditions. As a fictional concept, there is no standard composition; depictions range from oxides and chalcogenides to polymer-like networks.

Occurrence and synthesis: In-world narratives, natural deposits form under unique metamorphic conditions, or meltinu is produced in specialized furnaces with inert atmospheres. Rapid cooling traps a liquid into a metastable solid, while subsequent annealing tunes properties. Impurities strongly affect melting behavior.

Applications and limitations: Meltinu is used in thermal energy storage, heat switching, and actuators. In fiction, it offers rapid heat transfer and shape control, but practical issues include aging, phase separation, crystallization, and supply constraints.

Etymology: The name is built from the English word melt and a mineral-inspired suffix to convey origin; usage varies by author.