Abstract:The low carbon steel products with thickness of 2.0 mm and below produced in the short process of continuous casting and rolling are in great demand in the market. However, due to the factors such as rolling process and equipment capacity, the microstructure uniformity is poor, which further affects the product performance.The causes of the uneven microstructure of low carbon steel produced by ferritic rolling process are analyzed. It is found that the uneven microstructure of strip steel gradually increases with the thickness thinning. The strip steel with a thickness of 1.8 mm has uniform microstructure, but the uneven microstructure begins to appear from 1.5 mm, and the microstructure is obviously stratified when the thickness is reduced to 1.3 mm. When the thickness is reduced to 1.1 mm, the stratification gradually intensifies, showing a clear “sandwich” structure.The coiling temperature is increased from 650 ℃ to 680 ℃ by adopting the air cooling mode in the layer cooling section and putting in the insulation cover equipment. There is also a reduction in the thickness of the intermediate billet, the use of 70%-85% of the reduction rate and other measures, so that the uniformity of the organization has been significantly improved, compared with the previous performance, the yield is reduced by 3%-5%, the tensile strength is reduced by less than 3%, and the elongation is increased by 12%-29%.
李生存, 缪成亮, 田贵昌. 短流程连铸连轧低碳钢组织均匀性控制[J]. 连铸, 2024, 43(1): 62-66.
LI Shengcun, MIAO Chengliang, TIAN Guichang. Microstructure uniformity control of low carbon steel in short process continuous casting and rolling. CONTINUOUS CASTING, 2024, 43(1): 62-66.