Study On Inclusions Behavior In Steel Treated By Calcium

With the deepening of industrialization, steel consumption market’s requirements for the products performance increasingly stringent, iron and steel enterprises have also improved products quality-technical indicators. In the process conditions of large-scale production, The harm of non-metallic inclusions which stayed in liquid steel is not able to completely avoid. In order to minimize this hazard, calcium treatment technology had begun to appear in the Seventies of last century. This refining technology not only have been playing a very important role in steel deoxidizeing, desulfurizeing and inclusion transforming but also very effective in improving the steel cleanliness, reducing the extent of tumor which in outlet nozzle during continuous casting process, the liquid steel’s castability have been improved.In the specific in case of steel plant production process applications when the control of various steel chemical compositions, calcium treatment process can be broadly classified into two types: heavy calcium treatment and light calcium treatment.Calcium treatment is mainly used to improve the flow of molten steel, precautions ladle nozzle flow accumulator affect continuous casting production.In this paper, depending on a special issue of the steel plant— "Accurate Control of plate’s calcium treatment process", researching on LF refining process when calcium treatment working by calcium-related thermodynamics in liquid steel, the detection and analysis of inclusions compositions and morphology in sheet compare before calcium treatment to after calcium treatment. The innovation point in the paper,main contents of the work done and the conclusions of this article are as follows:1. Innovation point: The calcium treatment thermodynamic calculation about the inclusion in liquid steel is about the finished steel chemical composition, which in almost all found literature. However there are some differences between calcium treatment chemical composition and finished steel composition. The calculation in the paper is around the real-time chemical compositions when the calcium treatment start in LF refining.2. Main contents: Doing experiments to verify the real-time thermodynamic calculation, getting some samples from refining to continuous casting for analysis.3. Conclusion: The idea about improving the technology of calcium treatment is verified in the experiments, it’s truly can reduce the calcium line length, save the cost.