铸态厚壁高韧性球铁冷却壁的研制

Development of Thick-section Cooling Wall of As-cast High-toughness Ductile Iron

研究了硅、锰、磷等元素对冷却壁铸态力学性能的影响，比较了高稀土球化剂与低稀土球化剂的铸态生产应用效果。考察了浇包孕育与随流孕育对成分设计及铸态力学性能的影响，从而确定了高炉冷却壁的生产方案，据试验结果得出；化学成分为３．３～３．７％Ｃ，１．８～２．２％Ｓｉ，Ｍｎ≤０．２％，Ｐ≤０．０７％，Ｓ≤０．０３％；采用低稀土镁球化剂球化处理，加入量１．８～２．２％，使用冲入法处理；孕育处理为０．６～０．８％７５ＳｉＦｅ浇包孕育和０．２％７５ＳｉＦｅ块浮硅＋０．０２％ＲＣＡ随流孕育。

The effects of St, Mn, P on the mechanical properties of as-cast ductile iron coolingwall for blast furnace have been studied, the comparison was made on using high RE-Mgnodulizer and low RE-Mg nodulizer, the effects of the ladle inoculation and metal-streaminoculation on the composition design and as-cast mechanical properties were also discussed, thus determining optimum plan for manufacturing cooling wall of blast furnace,the results achived were: chemical composition, 3. 3 ～ 3. 7 %C, 1. 8- 2. 2 %Si, Mn≤0. 2 %, P≤0. 07 %, S≤0. 03 %. Nodularization treatment using low RE-Mg nodularizer,the amount of which is from 1. 8% to 2. 2% in sandwich process. Modification treatment, 0. 6～ 0. 8 %75SiFe in ladle inoculation and 0. 2%75SiFe+ 0. 02%RCA in metalstream inoculation.