RH精炼纯循环时间和镇静时间对IF钢洁净度影响

为了优化RH处理工艺,提高RH精炼后的IF钢的洁净度水平,通过分析全氧含量和夹杂物的控制水平,研究了纯循环和镇静时间对IF钢洁净度的影响。研究表明,RH加入铝粒反应6min后钢液中全氧质量分数降低至24.7×10~(-6)。加入Ti-Fe合金后,全氧质量分数上升至30×10~(-6)。随后RH经合金化后保持6~9min的纯循环时间,全氧质量分数可降低到27×10~(-6)。延长镇静时间至25min,可使全氧质量分数降低到27×10~(-6);通过直线法计算,夹杂物数量由破空时的13.21个/mm2逐渐降低到破空25min时的7.79个/mm2。

Effect of RH circulation time and holding time on cleanliness of IF steel

In order to optimize the RH treatment process and improve the cleanliness of IF steel,the influences of RH circulation time and holding time on the cleanliness of IF steel were studied through the analysis of TO]con-tent and inclusion content.The results show that TO]content decreases to 24.7×10-6 after adding Al for 6 min in RH.After adding Ti-Fe alloy,the TO]content increases to 30×10-6 .After RH alloying and circulation time for 6-9 min,the TO]content could decline to 27×10-6 .Extending the holding time to 25 min,the TO]con-tent could decrease to 27×10-6 and the number of inclusions decreases from 13.21 per square millimeter in broken time to 7.79 per square millimeter in 25 min after broken time.