球化铁水中氧的行为与球化衰退的关系

Relationship Between Oxygen Behavior and SpheroidalFading in the Spheroidal Graphite Liquid Iron

采用自行研制的铁水长期连续测氧探头，测定了球化铁水在共晶温度以上，高温等温保持过程中氧活度及其他冶金因素的变化；探讨了氧活度变化规律与球化衰退的关系。结果表明：球化铁水在高温保持过程中，氧活度不断增加，而ＲＥ，Ｍｇ，Ｓ含量降低；球化衰退是由于铁水中氧活度的增加，干扰和破坏了球状石墨生长过程引起的；脱硫、脱氧净化处理是有效的防止球化衰退的工艺方法。

With self-made oxygen probe,the changes of oxygen activity and other metallergical factors of spheroidal graphite liquid iron in the process of maintained temperature above the eutectic temperature are tested,and relationship between the oxygen activity and the spheroidal fading is also discussed.The results show that the oxygen activity of the spheroidal liquid iron increases,while the contents of RE,Mg and S decrease in the maintained high temperature;the spheroidal fading is caused by the increase of oxygen activity in the liquid iron,which interfer with and destroy the growth of spheroidal graphite,and that the purifying treatment of deoxidation and desulphurisation is efficient to preven s pheroidal fading.