Mechanism of inclusion evolution during refining process of 37Mn5 steel production
WANG Yi1, ZHANG Li-feng2, REN Ying1, REN Qiang1
1. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; 2. State Key Lab of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, Hebei, China
Abstract：The chemical compositions of non-metallic inclusions evolve during refining process and affect the performance of steel product.During the refining process of 37Mn5 steel production, the compositions of inclusions changed from Al2O3 to Al2O3-CaO-SiO2-MgO-CaS, without calcium treatment. Samples were taken from 37Mn5 steel plant for inclusion analysis to study the mechanism of inclusion evolution.The results showed there was a significant difference between the compositions of larger inclusions and smaller ones. The changing tendencies during the refining process varied in inclusions with different size groups. The inclusions with diameters larger than 10 μm had similar compositions to the refining slag. Thus these inclusions were caused by slag entrapment or peeling off of slag building-up. 1.17% calcium was detected in Fe-Si alloy, which resulted in a similar effect to calcium treatment, as a big amount of small size CaS inclusions were formed in a short time.The analysis of compositions, amounts, and morphologies of inclusions, slag compositions, and thermodynamic calculation indicated that inclusions evoluted due to deoxidation, refractory corrosion, slag entrapment, reactions between calcium and liquid steel, reacted between inclusions and liquid steel, the mechanism of inclusion evolution during the refining process of 37Mn5 steel production was revealed.
王祎, 张立峰, 任英, 任强. 37Mn5钢精炼过程夹杂物转变机理[J]. 钢铁, 2020, 55(5): 39-44.
WANG Yi, ZHANG Li-feng, REN Ying, REN Qiang. Mechanism of inclusion evolution during refining process of 37Mn5 steel production. Iron and Steel, 2020, 55(5): 39-44.
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