Cr_2O_3-Al_2O_3砖中不同组成Cr_2O_3-Al_2O_3电熔颗粒料的抗侵蚀研究

Corrosion resistance of fused Cr_2O_3-Al_2O_3 grains materials with different compositions in Cr_2O_3-Al_2O_3 bricks

首先以不同比例的铬绿和氧化铝粉电熔制得Cr2O3质量分数分别为15%、40%、50%、60%、85%、99%的6种Cr2O3-Al2O3电熔颗粒料（其编号依次为CR15、CR40、CR50、CR60、CR85和CR99）,然后采用回转渣蚀法研究了此电熔颗粒料（4~1 mm）的抗侵蚀性。结果显示：电熔颗粒料的抗侵蚀性随Cr2O3含量的增加及颗粒尺寸的增大而增强;高Cr2O3含量的CR99、CR85颗粒料在渣面层被侵蚀,主要是渣中的FeO和Al2O3对颗粒料的侵蚀,FeO与骨料中的Cr2O3反应,首先形成（Fe,Cr）3O4尖晶石,再与其他物相反应形成了复合尖晶石,当FeO耗尽后,渗入到颗粒内的Al2O3开始和Cr2O3反应,在颗粒表面形成铝铬固溶体;CR60颗粒料在渣面层和渗透层都存在侵蚀,渗透层的侵蚀主要是CaO、SiO2对颗粒料中铝铬固溶体中Al2O3的熔蚀,形成钙长石、钙黄长石以及玻璃相;Cr2O3含量较低的CR50、CR40、CR15颗粒料在渗透层内的侵蚀机制和CR60颗粒料的相同。

Six kinds of Cr2O3-Al2O3 fused grains materials（the mass percent of Cr2O3 was 15%,40%,50%,60%,85%,and 99%,respectively） were prepared using chrome green and Al2O3 powder as starting materials by electrofusion,named as CR15,CR40,CR50,CR60,CR85,and CR99,respectively.The corrosion resistance of the six kinds of materials（4-1 mm） was studied using rotary slag corrosion method.The results show that：（1）the corrosion resistance of the fused grains materials increases with the Cr2O3 content and the grain size increasing;（2）the grains of CR99 and CR85 with higher Cr2O3 content are corroded at the slag surface layer,because FeO and Al2O3 in the slag corrode the grains;the FeO reacts with Cr2O3 in aggregates forming（Fe,Cr）3O4 spinel firstly,and then reacts with other phases forming composite spinel;when the FeO is fully consumed,the Al2O3 penetrated into the grains reacts with Cr2O3 forming Al2O3-Cr2O3 solid solution on the grains surface;（3）for CR60,the corrosion exists both in the slag surface layer and the penetration layer,in the penetration layer,the CaO and SiO2 react with the Al2O3 in Al2O3-Cr2O3 solid solution forming anorthite,gehlenite,and glass phase;the grains of CR50,CR40,CR15 have the same corrosion mechanism with CR60 in the penetration layer.