80t BOF-LF-RH-CC流程冶炼55SiCr弹簧钢洁净度的研究

特殊钢 ›› 2016, Vol. 37 ›› Issue (4): 18-22.

80t BOF-LF-RH-CC流程冶炼55SiCr弹簧钢洁净度的研究

杜广巍^1,2，郭汉杰¹

1北京科技大学冶金与生态工程学院，北京100083；
2青海省工程咨询中心，西宁810001

收稿日期:2016-02-18 出版日期:2016-08-01 发布日期:2022-08-01
作者简介:杜广巍(1971-),男,博士生，高级工程师,1994年昆明工学院(本科)毕业，钢铁冶金研究。

A Study on Cleanliness of Spring Steel 55SiCr during 80t BOF-LF-RH-CC Steelmaking Process

Du Guangwei^1,2， Guo Hanjie¹

1 School of Metallurgical and Ecological Engineering, University of Science and Technology, Beijing 100083:
2 Qinghai Engineering Consulting Center, Xining 810001

Received:2016-02-18 Published:2016-08-01 Online:2022-08-01

摘要/Abstract

摘要： 55SiCr钢280 mm×325 mm铸坯（/%:0.55C,1.42Si,0.67Mn,0.008S,0.67Cr）的冶炼流程为80 t BOF-LF-RH-CC工艺。通过BOF出钢加Al和硅铁合金,同时加入精炼渣,控制精炼过程渣碱度R（CaO/SiO₂）为2.0左右,RH≥20 min,软吹搅拌≥15 min,控制钢中夹杂物转变,得到洁净弹簧钢55SiCr。分析结果表明,LF精炼过程中夹杂物由早期的Al₂O₃-SiO₂-MnO和Al₂O₃夹杂将逐渐转变为Al₂O₃-CaO-SiO₂夹杂,RH真空处理后夹杂物全部转变为Al₂O₃-CaO-SiO₂夹杂,LF开始精炼T[O]和[N]分别为36×10^-6和26×10^-6,铸坯T[O]、[N]分别为7×10^-6和43×10^-6,铸坯中夹杂物主要为Al₂O₃-CaO-SiO₂和Al₂O₃,尺寸≤10μm。

Abstract: The flowsheet for steelmaking of 280 mm x 325 mm casting bloom of steel 55SiCr (/% : 0.55C, 1. 42Si, 0. 67Mn, 0. 008S, 0. 67Cr) is 80 t BOF-LF-RH-CC process. With during BOF tapping adding Al, ferrosilicon and refining slag, controlling slag basicity R (CaO/SiO₂) about 2. 0, RH refining for ≥ 20 min, soft blowing stirring for ≥15 min to control the transformation of inclusions in steel, the clean spring steel 55SiCr is gotten. Analysis results show that during LF refining process the inclusions in liquid transformfrom earlier period Al₃O₃ -SiO₂-MnO and Al₂O₃ inclusions to inclusion Al₂O₃-CaO-SiO₂ , after RH vacuum treatment the inclusions in liquid all transform to inclusion Al₂O₃-CaO-SiO₂, the T[0] and [N] at beginning LF refining are respectively 36 x 10^-6and 26 x 10^-6 , and the T[0] and [N] in casting bloom are respectively 7 x 10^-6 and 43 x 10^-6 , and the inclusions in casting bloom are mainly Al₂O₃-CaO-SiO₃ and Al₂O₃ with size≤10μm

Key words: 80 t BOF-LF-RH-CC Flowsheet, Spring Steel 55SiCr, T[O], [N], Inclusions, Cleanliness

杜广巍, 郭汉杰. 80t BOF-LF-RH-CC流程冶炼55SiCr弹簧钢洁净度的研究[J]. 特殊钢, 2016, 37(4): 18-22.

Du Guangwei, Guo Hanjie. A Study on Cleanliness of Spring Steel 55SiCr during 80t BOF-LF-RH-CC Steelmaking Process[J]. Special Steel, 2016, 37(4): 18-22.