Results of the experiments on the crystallization of a Ge–Si–Sb solid solution under the conditions of microgravity on the Soyuz–Apollo spacecraft

Objective factors that allow the experiment on growing crystals of a Ge–Si–Sb solid solution on the Soyuz–Apollo spacecraft to take a special place among many experiments on growing single crystals aboard spacecrafts are analyzed. In the study of crystals grown on board a spacecraft, anomalous and unexpectedly high segregation of the solid solution components in the direction transverse to the direction of crystallization is found. An analysis of the obtained results allowed us, for the first time, to establish a causal relationship between anomalous segregation and microgravity features on board a spacecraft. Determining the physical nature of anomalous segregation have affected the direction of further research and give rise to an in-depth study of specific features of the new technological environment, the rapid development of numerical methods for studying heat and mass transfer processes in melts, and the expanding of the range of studied crystals and methods for studying them. A great contribution to the development of this area was made by Professor V.S. Zemskov.