矾土骨料种类对铝镁浇注料性能的影响

Effects of bauxite aggregate type on properties of Al_(2)O_(3)-MgO castables

分别以86级矾土均化料和88级传统倒焰窑矾土熟料为骨料制备了MgO-SiO_(2)-H_(2) O结合铝镁浇注料,采用动态感应炉抗渣试验,通过SEM、EDS分析和FactSage 6.2热化学软件对浇注料的侵蚀结果进行分析。结果表明:(1)以倒焰窑矾土为骨料的试样抗渣渗透性优于以均化矾土为骨料的试样,但两种浇注料的抗渣侵蚀性能相差不大;(2)渣蚀后以均化矾土为骨料的试样接近热面附近的骨料周围会生成较大的裂纹,对试样的抗渣性能产生不利影响,而以倒焰窑矾土为骨料的试样没有观察到裂纹生成;(3)以倒焰窑矾土为骨料的试样和以均化矾土为骨料的浇注料试样与熔渣反应后,有刚玉、复合尖晶石、CA_(6)、C_(2)AS、CAS_(2)等相共存。

MgO-SiO_(2)-H_(2) O based Al_(2)O_(3)-MgO castables have been prepared with 86%Al_(2)O_(3) homogenized bauxite and 88%Al_(2)O_(3) down-draft kiln bauxite as aggregates,respectively.The slag resistance of the castable specimens was investigated by a dynamic testing method via an induction furnace,and the results were studied by SEM,EDS and FactSage 6.2 thermodynamic modeling.The results show that the slag penetration resistance of castable with 88%Al_(2)O_(3) down-draft kiln bauxite is a little better than the castable with 86%Al_(2)O_(3) homogenized bauxite,and there is not much difference on slag resistance between the two castables;Cracks were formed at the aggregate-matrix interface near the hot face after the corrosion test,which adversely affects the slag resistance of the sample;After the above two castables respectively reacted with the slag,corundum,composite spinel,CA_(6),C_(2)AS and CAS_(2) were coexsited.