In view of process conditions of Vanadium Recovery and Steelmaking Plant, PanGang Group Panzhihua steel and Vanadium Co.,Ltd., and on the basis of making choice of a reasonable deoxidization process, some measures hav...In view of process conditions of Vanadium Recovery and Steelmaking Plant, PanGang Group Panzhihua steel and Vanadium Co.,Ltd., and on the basis of making choice of a reasonable deoxidization process, some measures have been taken to the development of automobile gear steel (20CrMoH) such as the pre-refining technology during converter tapping, "white slag" refining in LF, RH Vacuum treatment, and even protective casting technology. Also different and suitable models of argon blowing from bottom of ladle were adopted in the platform after converter, LF refining and calcium treatment. Test results show that the high cleanness 20CrMoH gear steel slab with T[O] ≤15×10-6(The average T[O] is 11.8×10-6) could be obtained through all these measures.展开更多
A numerical model of heat transfer was developed to investigate the heat transfer of continuously cast billet with the aid of surface temperature tests by ThermaCAMTM researcher and nail shooting experiments. The effe...A numerical model of heat transfer was developed to investigate the heat transfer of continuously cast billet with the aid of surface temperature tests by ThermaCAMTM researcher and nail shooting experiments. The effects of secondary cooling practice and casting speed on the solidification process and central segregation of carbon were investigated as well with the actual central segregation tests. The results show that the surface center and billet center temperatures exhibit a different pattern during solidification, and the solidified shell thickness is presented as an ＂S＂ type. With the increase of secondary cooling intensity and the decrease of casting speed, the end points of the solidus line and the liquidus line move forward, and the central segregation level of carbon decreases. The optimal casting condition is suggested for continuously cast high carbon billet with F-EMS （final electromagnetic stirring）.展开更多
文摘In view of process conditions of Vanadium Recovery and Steelmaking Plant, PanGang Group Panzhihua steel and Vanadium Co.,Ltd., and on the basis of making choice of a reasonable deoxidization process, some measures have been taken to the development of automobile gear steel (20CrMoH) such as the pre-refining technology during converter tapping, "white slag" refining in LF, RH Vacuum treatment, and even protective casting technology. Also different and suitable models of argon blowing from bottom of ladle were adopted in the platform after converter, LF refining and calcium treatment. Test results show that the high cleanness 20CrMoH gear steel slab with T[O] ≤15×10-6(The average T[O] is 11.8×10-6) could be obtained through all these measures.
基金Sponsored by National Natural Science Foundation of China(50925415)Fundamental Research Funds for Central University of China(N100102001)
文摘A numerical model of heat transfer was developed to investigate the heat transfer of continuously cast billet with the aid of surface temperature tests by ThermaCAMTM researcher and nail shooting experiments. The effects of secondary cooling practice and casting speed on the solidification process and central segregation of carbon were investigated as well with the actual central segregation tests. The results show that the surface center and billet center temperatures exhibit a different pattern during solidification, and the solidified shell thickness is presented as an ＂S＂ type. With the increase of secondary cooling intensity and the decrease of casting speed, the end points of the solidus line and the liquidus line move forward, and the central segregation level of carbon decreases. The optimal casting condition is suggested for continuously cast high carbon billet with F-EMS （final electromagnetic stirring）.
