Fe2O3粉加入量对镁钙质中间包干式料性能的影响

以w(CaO)≈20%的镁钙砂(其粒度为5～3、3～1、1～0.2、≤0.2和≤0.074 mm)为主原料制成镁钙质中间包干式料,并研究了加入不同量Fe2O3粉(其质量分数分别为0、1%、2%、3%、4%)对干式料性能的影响。结果表明:1)加入Fe2O3粉可以增加镁钙质干式料的低温和中温强度,但加入质量分数超过3%后,干式料的低温强度明显下降,高温烧后显气孔率上升,体积密度下降,体积膨胀加剧;综合分析认为,镁钙质干式料中Fe2O3粉的加入质量分数在2%～3%较适当。2)加入Fe2O3粉的镁钙质干式料抗熔渣侵蚀性能较好,这是由于加入的Fe2O3与镁钙砂中的CaO反应生成了低熔点矿物铁酸二钙,促进了材料的烧结,从而提高了其抗熔渣侵蚀性。

Effects of Fe2O3 powder additions on properties of magnesia-calcia dry materials for tundish

The magnesia-calcia dry materials for tundish were prepared using magnesia-calcia sands(w(CaO) is about 20%,particle sizes are 5-3 mm,3-1 mm,1-0.2 mm,≤0.2 mm and ≤0.074 mm,respectively) as main starting materials.Effect of Fe2O3 powder additions(0,1%,2%,3% and 4% in mass,respectively) on performance of magnesia-calcia dry materials was researched.The results show that:(1)adding Fe2O3 can increase the strengths of the dry materials at low and middle temperatures;when the Fe2O3 addition exceeds 3%,the low temperature strength decreases obviously,for the dry materials fired at high temperatures,the apparent porosity rises,bulk density decreases and the volume dramatically expands;the optimal addition of Fe2O3 powder is 2%-3%;(2)the dry materials with Fe2O3 powder perform good corrosion resistance to molten slag,because Fe2O3 reacts with CaO of magnesia-calcia sand forming dicalcium ferrite with low melting point,which accelerates the sintering.