Development of micro-encapsulated phase change materialsusing al-based alloy for high temperature applications

Abstract

This manuscript described the development of core-shell type micro-encapsulated phase change materials (MEPCM) using Al-based alloy as a phase change material (PCM) for high temperature applications. Al-25 mass% Si microspheres (diameter: 75~90 μm, melting temperature: 577°C) was used as core material (=PCM). The MEPCM was prepared in two steps. First step is the formation of AlOOH precursor shell on the PCM microspheres in boiling distilled water. Second step is heat-oxidation treatment in an O2 atmosphere to form a stable Al2O3 shell. The effects of heat-oxidation temperature (1150–1350°C) on the shell morphology and heat storage performance, were mainly investigated. As results, MEPCMs were successfully prepared and the shell compositions were single α-Al2O3 phase regardless of different heat oxidation temperature. The heat capacities of the as prepared MEPCMs were over 4 times higher than that of conventional heat storage materials. The MEPCM developed in this study has great promise in future energy utilization processes.