不同铝含量的脱氧剂对钢液洁净度的影响

作者:Zhao Yi-Jiang; Li Guang-Qiang; Meng Ze; Wang Xi-Jie; Zhao Rui; Liu Yu*
来源:Kang T'ieh/Iron and Steel, 2023, 58(1): 47-54and90.
DOI:10.13228/j.boyuan.issn0449-749x.20220436

摘要

Al possesses strong deoxidation ability, thus is widely used in the deoxidation of molten steel during steel-making. However, the high melting point and large size Al2O3inclusions produced by Al deoxidation will not only seriously reduce the cleanliness of molten steel, and deteriorate the toughness and fatigue life of steel, but also easily cause nozzle nodules, which will affect the continuous casting process. Considering that local supersaturation has an important effect on the nucleation and growth of inclusions, pure Al and Fe-SOlMiAl alloy (mass percent) were used to deoxidize the molten steel, and the actual amount of Al addition was consistent, and the effect of Al contents on the cleanliness of the molten steel was studied by analyzing the molten steel composition and inclusion characteristics of different deoxidation times (30, 60 s). The results show that compared with pure Al deoxidation, Fe-30%A1 alloy has better deoxidation effect, and the dissolution rate of Al element in the alloy is slower. In addition, the maximum size of inclusions in the steel samples deoxidized with pure Al can reach 9 μm, while that in the test of Fe-30% Al alloy is only 4 μm, The average size of inclusions in the steel after pure Al deoxidation for 60 s is 1. 35 times that of Fe-30% Al alloy deoxidation, and the number of inclusions per unit area is increased by 23%. The inclusions remained in the molten steel during the deoxidation process of the two deoxidizers are mainly polyhedral inclusions, and there are some loose cluster-like inclusions formed by collision and aggregation. Deoxidation of molten steel with Fe-30% Al alloy is more effective than that with pure Al, which depends on different local supersaturation in the initial deoxidation process. ? 2023 Chinese Society for Metals.