CeO_2添加对Ta_2O_5低膨胀陶瓷结构与性能的影响  

Influence of CeO_2 Addition on Structure and Properties of Ta_2O_5-based Low Expansion Ceramics

作　　者：李月明[1] 江瑜华[1] 许素芳[1] 张小珍[1] 周健儿[1] 

机构地区：[1]景德镇陶瓷学院材料科学与工程学院,江西省先进陶瓷材料重点实验室,景德镇333403

出　　处：《人工晶体学报》2013年第7期1371-1375,共5页Journal of Synthetic Crystals

基　　金：江西省科技支撑计划项目(20112BBE5009)

摘　　要：采用干压成型和高温固相反应烧结制备了CeO2改性Ta2O5低膨胀陶瓷材料。研究了CeO2加入量对制备的Ta2O5陶瓷样品的物相组成、微观结构、热膨胀性能、抗折强度和抗热震性能等的影响。结果表明,经1450℃保温2h烧成,纯Ta2O5陶瓷由β-Ta2O5组成,存在明显的开裂现象,表现出负的热膨胀系数(-1.02×10-6℃-1)和低的抗折强度(1.69 MPa)。添加CeO2后,除β-Ta2O5主晶相外,还生成了六方相针状CeTa7O19晶体。适量CeO2的加入可有效抑制Ta2O5陶瓷的高温可逆相转变和消除开裂现象,形成致密的微观结构,样品呈现低的正热膨胀系数,抗折强度和抗热震性能显著提高。CeO2 modified Ta2O5 ceramic materials were prepared by dry pressing and high temperature solid-state sintering techniques.The influences of CeO2 content on the phase composition,microstructure,thermal expansion performance,flexural strength and thermal shock resistance of prepared Ta2O5 ceramic samples were investigated.The results indicated that the pure Ta2O5 ceramic,composed of orthorhombic phase β-Ta2O5,shows obvious microcracking phenomena and exhibits negative thermal expansion coefficient（-1.02 × 10-6℃-1） and low flexural strength（2.11 MPa） after sintered at 1450 ℃ for 2 h.Hexagonal phase CeTa7O19 acicular crystals as minor phase were formed with the addition of CeO2.The addition of appropriate amout of CeO2 could effectively inhibit the high temperature reversible phase change and avoid producing microcracks to form a dense microstructure.The prepared CeO2 modified Ta2O5 ceramic samples demonstrate low and positive thermal expansion coefficient,significantly increased flexural strength and thermal shock resistance.

关 键 词：低膨胀陶瓷 TA2O5 CEO2 热膨胀系数 抗折强度 

分 类 号：TQ174[化学工程—陶瓷工业]