Characterization of Heat Transfer in Solidification Experiments of Lightweight High-entropy Alloys on Chinese Space Station

Abstract

Owing to the difference in convective heat transfer mechanisms between space and ground, the temperature profile of lightweight high-entropy alloys (HEAs) in space is different from the ground which may prevent the samples from melting as intended and thus cause the space experiment to fail. To predict the temperature profile and obtain the heat transfer characteristics in space, it employed experimental temperature data of the standard SCA at 800 °C under both ground and space. Specifically, numerical models of the high-temperature furnace and SCA were established, and different operating conditions and relevant thermophysical parameters were adjusted to conduct the thermal simulations of the temperature profile of the SCA in space and on ground. The respective heat transfer characteristics for space and ground were thus obtained. Based on the obtained heat transfer characteristics, the temperature profile and heat transfer characteristics of the lightweight HEA experiment in space were predicted when the furnace temperature is 900 °C, the target experimental temperature from the ground-based HEA experiment. The results provide an important foundation for conducting HEA solidification experiments in microgravity.