| 摘要 |
PURPOSE:To reasonably perform the molten metal production of a high Cr alloy steel by a method wherein the processes for de-Si, De-P, and de-S of hot metal and slag discharging are done in one operation, and the use of Ar and CaO is decreased in the bottom-blown decarburization process. CONSTITUTION:A one-time treatment is performed for the processes of de-Si, de-P, and de-S of hot metal, by bcombining a Na2CO3-based flux and an oxidizing agent such as O2 or iron oxide. In this process, P is reduced below 0.015% and S below 0.015%, and the slag discharge process is done in one operation to reduce the loss in heat and yield. Furthermore, a converter having a bottom blown function is used to perform more effective de-C operation so as to reduce the use of Ar and to control the slag basicity to 1.4=CaO/SiO2 1.7 at the finishing decarburization process. The content of MgO is controlled high for low basicity and low for high basicity, in the range of 5-15%; this reduces the amount of slag, the concentration of chromium oxide in slag, and therefore Cr loss in slag, thereby effecting a reasonable high-Cr alloy steel production. |
