Thermal capacitors made from miscibility gap alloys (MGAs)

Abstract

The current paper addresses the thermal characterisation of Miscibility Gap Alloys (MGAs). These novel materials combine two immiscible metallic phases with different melting temperatures. The fusible phase (i.e. the phase with a lower melting temperature) acts as a phase change material that stores latent heat (in addition to sensible heat) thus optimising energy storage capacity. The second phase forms an enclosure and prevents the leakage of liquid material. Due to the high inherent thermal conductivity of metals, MGAs exhibit excellent thermal conduction in comparison to traditional phase change materials such as hydrate salts or paraffin. The combination of high energy storage and fast heat transfer makes MGA uniquely suited for use as thermal capacitors in applications like space heating, concentrated power generation or temperature stabilisation of sensitive equipment. The current paper determines the thermal properties of MGAs using Lattice Monte Carlo analysis combined with micro-computed tomography imaging.