Abstract: Vacuum degassing (VD) refining, characterized by strong reactions between slag and steel within a vacuum atmosphere, serves functions such as degassing, desulfurization, and the control of non-metallic inclusions. This method is of great importance for producing high-quality clean steel. This work presented an overview of the development history and industrial applications of VD refining technology, described in detail the research and production of VD refining in degassing, desulfurization and inclusion control, and gave some suggestions for this process at the end. In VD refining, researches on vacuum degassing (including O, N, H) mainly focused on optimizing process parameters and enhancing equipment performance. It could control [H] in steel within (1-2)×10^-6 and [N] within (40-60)×10^-6, and denitrogen in VD had some advantages. Regarding desulfurization, VD refining benefitted from favorable thermodynamic and kinetic conditions, enabling control of [S] in steel at relatively low levels. In terms of inclusion control, VD process could decrease the quantity of inclusions effectively and modify inclusions through optimizing slag compositions and process parameters. The related research results had certain guiding significance for the research and industrial production of VD refining, offering favorable references for reducing impurity element content, controlling non-metallic inclusions, as well as improving steel cleanliness.

Key words: VD refining, vacuum degassing, desulfurization, inclusion control, refining slag