Y-PSZ加入量对方镁石-尖晶石质耐火材料性能的影响

摘要

为了改善方镁石-尖晶石质耐火材料的性能,以高纯镁砂颗粒(5～2和≤2 mm)、电熔镁砂细粉(≤0.088 mm)和预合成烧结富镁尖晶石(≤1 mm)为主要原料,以Y-PSZ为添加剂,经1 650℃保温3h烧成了方镁石-尖晶石试样,研究了Y-PSZ加入量(w)为0、0.5％、1.0％、1.5％、2.0％时对该材料性能的影响.采用国标进行各项性能检测,采用X射线衍射仪和扫描电镜-能谱仪做显微结构分析.结果表明:1)烧成后,ZrO2由单斜相转变为四方相;2)随着Y-PSZ的加入,试样的抗热震性得到显著提高;3)从显微结构照片可以看出,加入Y-PSZ后方镁石晶粒明显长大,同时试样的断裂机制由穿晶断裂转变为沿晶断裂.当Y-PSZ的加入量(w)为0.5％ ～1.0％时,试样的综合性能最优.%In order to improve the properties of periclase-spinel refractories,the specimens were prepared using high purity magnesia particle (5-2,≤2 mm),fused magnesia fines (≤0.088 mm),and pre-synthesized sintered magnesia-rich spinel (≤1 mm) as starting materials,Y-PSZ as an additive,fired at 1 650 ℃ for 3 h.Effects of Y-PSZ additions (0,0.5％,1.0％,1.5％,and 2.0％,by mass,the same hereinafter) on properties of the specimens were researched.The results reveal that:(1) after sintering,ZrO2 transforms from monoclinic to tetragonal;(2) adding Y-PSZ,the thermal shock resistance improves obviously;(3) according to microstructure,adding Y-PSZ,the periclase grains grow greatly,and the fracture mechanism changes from transgranular fracture to intergranular fracture.The properties of specimen are the optimal with 0.5％-1.0％ Y-PSZ.