稀土La2O3添加对氧化铝多孔陶瓷性能的影响  

Effect of Rare Earth La2O3 Addition on Properties of Alumina Porous Ceramics

作　　者：杨政金 李晓鸿 陈璐[1] 白首金 徐兆芳 帅树乙 黎阳[1] YANG Zhengjin;LI Xiaohong;CHEN LU;BAI Shoujin;XU Zhaofang;SHUAI Shuyi;LI Yang(School of materials and architectural engineering,Guizhou normal university,Guiyang 550025,China)

机构地区：[1]贵州师范大学材料与建筑工程学院,贵阳550025

出　　处：《中国陶瓷》2020年第1期12-17,共6页China Ceramics

基　　金：贵州师范大学创新创业项目(2017039);贵州省教育厅自然科学基金项目([2015]363);国家自科学基金项目(51462004)。

摘　　要：以煅烧α-Al2O3为原料,稀土氧化镧(La2O3)为添加剂,羧甲基纤维素为成型粘结剂,通过混料、困料、研磨、模压成型、高温烧结等工序制备了氧化铝多孔陶瓷,研究了烧结温度及La2O3添加量对氧化铝多孔陶瓷的线收缩率、体积密度、孔隙率、抗折强度和微观形貌的影响。结果表明:在相同烧结温度下,随稀土添加量的增加,多孔陶瓷的体积密度、线收缩率与抗折强度均降低,而孔隙率则逐渐增加。微观形貌与X衍射分析表明,稀土La2O3的加入,抑制了氧化铝颗粒间的烧结,并在高温下与氧化铝反应生成了片状晶体LaAl11O18,片状晶LaAl11O18阻碍了氧化铝晶粒的长大,进而抑制了坯体的收缩,最终使得氧化铝多孔陶瓷具有较高的孔隙率。Alumina porous ceramics were prepared by using calcined α-Al2O3 as raw material, rare earth La2O3 as additive, carboxymethy cellulose as molding binder with process of mixing, aging, grind, molding and sintering. The effects of sintering temperature and La2O3 addition amount on the linear shrinkage, volume density, porosity, flexural strength and microstructure of the porous alumina ceramics were studied. Results showed that the volume density, linear shrinkage and flexural strength decreased with increasing rare earth content at the same sintering temperature, while the porosity increased. As indicated in the microstructure and XRD patterns, the La2O3 restrained the sintering effect among the alumina particles. The tabular crystal LaAl11O18 was formed by reaction between the Al2O3 and La2O3 at high temperature. The tabular crystal LaAl11O18hindered the crystal grain increase and resulted in higher porosity.

关 键 词：煅烧α-Al2O3 稀土氧化镧 氧化铝多孔陶瓷 烧结 

分 类 号：TQ174.758.11[化学工程—陶瓷工业]