轻烧MA90尖晶石加入量对刚玉-尖晶石浇注料显微结构和性能的影响

摘要

通过固定尖晶石总含量(质量分数23．5％),改变轻烧和死烧MA90尖晶石质量比制备了不同轻烧尖晶石含量的刚玉-尖晶石浇注料,在1600℃下进行了钢包渣侵蚀试验,研究了轻烧尖晶石含量对该浇注料显微结构和抗渣性能的影响.结果表明：随着轻烧尖晶石质量分数从0增加到23．5％,浇注料的线收缩率增大、显气孔率和体积密度基本不变、强度降低；侵蚀后基体中出现裂纹,且轻烧尖晶石含量较高的裂纹较多；随着轻烧尖晶石含量的增加,浇注料的抗渣侵蚀性逐渐降低,抗渣渗透性逐渐增强；当轻烧尖晶石质量分数为17．6％时,其综合性能最好,显气孔率为15．7％,抗折和耐压强度分别为26．9,107．8 MPa,侵蚀指数和渗透指数分别为0．32和0．91.%The corundum-spinel castables with different light-burned spinel content were prepared by fixing total spinel content of 23.5wt% and changing the mass ratio of light-burned and dead-burned MA90 spinel,and then the ladle slag corrosion tests were conducted at 1 600 ℃.The microstructures and slag resistance of the castables were studied.The results show that with the light-burned spinel content increased from 0 to 23.5wt%,the linear shrinkage of the castables increased,the apparent porosity and volume density remained unchanged,and strengths decreased.The cracks were observed in the uncorroded matrix and more cracks were observed in the matrix with a higher content of light-burned spinel after corrosion.With the increase of light-burned spinel content,the slag corrosion resistance of the castables decreased while the slag penetration resistance increased.When the light-burned spinel content was 17.6wt%,the specimen had the optimum performance,which was with the porosity of 15.7%, flexural strength of 26.9 MPa,crushing strength of 107.8 MPa,slag corrosion index of 0.32 and penetration index of 0.91.