Optimization of Mold Powders for High‐Nitrogen Stainless Steel Based on Mold Thermocouple Temperature Variation

作者：Fuhang Chen, Guanghua Wen, Ping Tang, Zibing Hou, Youyu Lu, Peng Cheng, Qingmao Kong · 发表于：steel research international · 年份：2023 · DOI：10.1002/srin.202300154 · 被引用次数：6 · 研究领域：Metallurgical Processes and Thermodynamics、Hydrogen embrittlement and corrosion behaviors in metals、Microstructure and Mechanical Properties of Steels

High‐nitrogen stainless steel (HNSS) is prone to surface depression during continuous casting; however, its high‐temperature solidification characteristics and mold powder design have not been reported. Based on the analysis of mold thermocouple temperature variation, this study clarifies the high‐temperature solidification characteristics of HNSS and the cause of surface depression. It optimizes the mold powder for HNSS continuous casting according to factory and laboratory research. The factory trials indicate that the mold thermocouple temperature at the corresponding location decreases by 6.0–20.9 °C when the slab surface is depressed. The analysis shows that the high initial solidification strength of HNSS causes its slab surface depressions. Owing to this characteristic, the mold powder for HNSS should have a suitable melting rate, low basicity, and proper Al 2 O 3 . This low‐basicity Al 2 O 3 ‐containing slag has a crystal slag film near the mold side and a thick liquid slag film near the slab. It can both provide good lubrication and control horizontal heat transfer.