Research on Measurement Method of Solid-Liquid Interface in Space Material Science Experiment

Abstract:
The microgravity environment greatly reduces the gravity-driven natural convection, settlement and hydrostatic pressure, it is helpful to study the solidification process and related mechanisms of materials under nearly pure diffusion control conditions. In order to better understand and analyze the solidification process of materials, it is necessary to obtain the solidification process parameters that have an important influence on the solidification process of the material, such as the moving speed of the solidification interface. But limited by resources and technical conditions, no relevant data has been obtained in the space material science experiments that China has carried out in the past. This makes it difficult for the follow-up anatomical analysis of the experimental results of space materials to be in-depth. At present, China space station has been launched, and a large number of space material science experiments will be carried out on China space station in the next ten years. In order to improve the technical level of China's space materials science, provide scientists with more abundant online process data to facilitate the follow-up in-depth analysis of the results of space experiments. In this paper, an experimental system for monitoring the solid-liquid interface of the material is designed, and the experimental method of online detection is realized. The directional solidification experiment is carried out using pure aluminum samples in a high-temperature resistance furnace. Through the experimental method of ultrasonic pulse, the solid-liquid interface position was calculated.