稳定剂对ZrO2质定径水口基质烧成前后相组成和显微结构的影响∗

摘要

ZrO2 sizing nozzle matrix was researched by adding stabilizer which were 2.8%MgO,2.1%MgO and 2.2%MgO+1%Y2 O3 respectively in the desilication zirconium powder.The effects of stabilizer on the composi-tion of phase and the microstructure of ZrO2 sizing nozzle matrix before and after sintering were studied by XRD,SEM and EDS.Results showed that the content of cubic phase increased and the content of monoclinic phase decreased significantly for all samples after sintering at 1 630 ℃,the specise and feed ratio of stabilizer in raw materials made cubic and monoclinic phase variation of each sample were not the same after sintering;After sintering at 1 630 ℃,the solid solution was formed by MgO and ZrO2 ,with the location of MgO particle clos-er,the substitution degree of Mg2+ and Zr4+ was more obvious,but the diffusion and solid solution of the stabi-lizer were far from uniform state;For the sinteried sample combining MgO+Y2 O3 stabilizer,cubic phase gained the most,and solid solution generated largest,the degree of stabilization was the highest and the combi-nation between ZrO2 particles which have uniform size and angular shape is much close.%以ZrO2质定径水口基质为研究对象，在脱硅锆细粉中添加稳定剂，其中稳定剂的种类和加入量分别为2．8％MgO、2．1％MgO、2．2％MgO＋1％Y2 O3.借助XRD、SEM和EDS等检测手段，研究了稳定剂对ZrO2质定径水口基质烧成前后相组成和显微结构的影响.结果表明，试样经1630℃烧成，各试样立方相含量明显增加，单斜相含量明显减少，原料中稳定剂的种类和加入量的不同使得烧成后各试样立方相和单斜相的变化量也不相同；试样经1630℃烧成，稳定剂MgO 与ZrO2形成固溶体，越靠近 MgO 颗粒的位置Mg2＋与Zr4＋的替换程度越明显，但稳定剂的扩散固溶远未达到均匀状态；以MgO＋Y2 O3为稳定剂的试样，烧成后立方相的增加量最多，固溶体的生成量最大，稳定化程度最高，且 ZrO2颗粒的尺寸大小均匀，棱角分明，颗粒之间的结合非常紧密.