Ligature synthesis by aluminothermic reduction of ytterbium oxide with the formation of nanoscale intermetallides

As part of the development of critical technologies, it is necessary to search for alternative replacement of components in the compositions of aluminum ligatures, including known modifying additives of scandium and yttrium with other rare-earth and rare elements. Aluminum ligatures with rare-earth metals are widely considered in many scientific papers, but the research on the production of Al-Yb ligatures is limited. In this paper, the authors describe the results of studying the production of ligatures of the aluminum-ytterbium system from ytterbium oxide by aluminothermic reduction, containing nanoscale Al3Yb intermetallic compounds and eutectics in their structure. Serving as crystallization centers, the optimal-size particles of intermetallic compounds provide uniform fine-grained structure in aluminum alloy castings. The relationship has been obtained that enables the maximum transition of ytterbium into the alloy depending on the quantitative and qualitative composition of the reaction mixture and various melting process parameters. The conducted studies have shown that ligatures obtained by aluminothermic reduction of ytterbium oxide with the addition of 5 to 15 wt. % Mg to the reaction mixture have the highest characteristic of ytterbium transition into the ligature.