The optimization of flow control devices in a single-slab continuous casting tundish was carried out by physical modeling, and the optimized scheme was presented. With the optimal tundish configuration, the minimum re...The optimization of flow control devices in a single-slab continuous casting tundish was carried out by physical modeling, and the optimized scheme was presented. With the optimal tundish configuration, the minimum residence time of liquid steel was increased by 1.4 times, the peak concentration time was increased by 97%, and the dead volume fraction was decreased by 72%. A mathematical model for molten steel in the tundish was established by using the fluid dynamics package Fluent. The velocity field, concentration field, and the resi-dence time distribution (RTD) curves of molten steel flow before and after optimization were obtained. Experimental results showed that the reasonable configuration with flow control devices can improve the fluid flow characteristics in the tundish. The results of industrial applica-tion show that the nonmetallic inclusion area ratio in casting slabs is decreased by 32% with the optimal tundish configuration.展开更多
The effects of chemical compositions, especially silicon and chromium contents, on the complete decarburization behaviors of steels in atmosphere of 2 vol. %O2 and 98 vol. % N2 were investigated by using a simuhaneous...The effects of chemical compositions, especially silicon and chromium contents, on the complete decarburization behaviors of steels in atmosphere of 2 vol. %O2 and 98 vol. % N2 were investigated by using a simuhaneous thermal analyzer. Complete decarburization was observed at both 750 and 800 ℃ for 60Si2MnA steel, while 750℃ only for 92A steel. For GCr15 steel, no decarburization was found at 750 or 800 ℃, and only partial decarburization was observed at 850 ℃. It indicates that silicon promotes while chromium prevents the complete decarburization of steels in atmosphere with 2 vol. % O2. The main reason is that silicon increases while chromium reduces the equilib rium concentration of ferrite at the interface of ferrite and austenite, which results in the complete decarburization.展开更多
文摘The optimization of flow control devices in a single-slab continuous casting tundish was carried out by physical modeling, and the optimized scheme was presented. With the optimal tundish configuration, the minimum residence time of liquid steel was increased by 1.4 times, the peak concentration time was increased by 97%, and the dead volume fraction was decreased by 72%. A mathematical model for molten steel in the tundish was established by using the fluid dynamics package Fluent. The velocity field, concentration field, and the resi-dence time distribution (RTD) curves of molten steel flow before and after optimization were obtained. Experimental results showed that the reasonable configuration with flow control devices can improve the fluid flow characteristics in the tundish. The results of industrial applica-tion show that the nonmetallic inclusion area ratio in casting slabs is decreased by 32% with the optimal tundish configuration.
文摘The effects of chemical compositions, especially silicon and chromium contents, on the complete decarburization behaviors of steels in atmosphere of 2 vol. %O2 and 98 vol. % N2 were investigated by using a simuhaneous thermal analyzer. Complete decarburization was observed at both 750 and 800 ℃ for 60Si2MnA steel, while 750℃ only for 92A steel. For GCr15 steel, no decarburization was found at 750 or 800 ℃, and only partial decarburization was observed at 850 ℃. It indicates that silicon promotes while chromium prevents the complete decarburization of steels in atmosphere with 2 vol. % O2. The main reason is that silicon increases while chromium reduces the equilib rium concentration of ferrite at the interface of ferrite and austenite, which results in the complete decarburization.