Abstract:

Directed against the performance degradation problem of domestic car plate steel due to increasing Si in molten steel during the smelting process, in this paper, the changes in the production of Si content in each smelting stage were studied. The influence factors of the molten steel raising Si mainly include slag basicity, and aluminum content in molten steel, tundish slag and tundish insulation material, etc. By the measures of choosing deoxidizer with Si content less than 1.5%, improving slag basicity by using the modification agent, and adopting alkali tundish, the mass fraction of molten steel increasing Si was controlled below 0.01% during the refining and continuous casting process.

Key words: Si content, slag basicity, vacuum decarburization