铬酸镧/氧化铝复合材料的烧结机制与性能  

Properties and Sintering Mechanism of LaCrO_3/Al_2O_3 Composites

作　　者：纪元[1] 孙良成[2,3] 杨忠贤 朱新德[1] 

机构地区：[1]山东大学材料科学与工程学院,山东济南250061 [2]包头稀土研究院,内蒙古包头014030 [3]稀土冶金及功能材料国家工程研究中心,内蒙古包头014030 [4]兵器工业部第52研究所,内蒙古包头014014

出　　处：《稀土》2010年第5期28-32,共5页Chinese Rare Earths

基　　金：高等学校博士学科点专项科研基金(20050422026)

摘　　要：将掺Ca铬酸镧与Al2O3混合,在1650℃烧结得到氧化铝量从0~100%（摩尔分数）的系列Al2O3/La0.9Ca0.1CrO3复合材料烧结体。研究得出Al2O3/La0.9Ca0.1CrO3系统是热力学不稳定的,高温烧结时存在离子扩散,烧结体的最终相组成与Al2O3量有关。复合材料中氧化铝含量较低时（≤20%,摩尔分数）可以提高铬酸镧粉体的烧结性能;当氧化铝含量在30%~70%（摩尔分数）之间时,生成的层片状六铝酸镧使烧结致密度降低,并在氧化铝含量为70%（摩尔分数）时达到最低值,随后试样的相对密度又逐渐增大。A series of Al2O3/La0.9Ca0.1CrO3 composite sintered bodies were prepared by sintering the mixture of Ca-doped lanthanum chromate and alumina at 1650 ℃,with content of Al2O3 from 0 to 100 mol%.It was generalized that the system of Al2O3/La0.9Ca0.1CrO3 results in thermodynamic unstablity with visible cation diffusion at high temperature,and the final phase composition of sintered bodies depends on the alumina content.Alumina addition with low content（≤20mol%）） in the composite can improve the sintering property of La0.9Ca0.1CrO3 powders.When Al2O3 content is between 30mol% and 70mol%,plate-like lanthanum hexaaluminate is generated,which can cause the lower degree of density to the sintered bodies.The relative density reaches its minimum value when Al2O3 content is 70mol% and gradually increases with the increasing of α-Al2O3 content.

关 键 词：铬酸镧 氧化铝 复合材料 烧结 

分 类 号：TQ133.3[化学工程—无机化工]