MgO掺杂对稀土锆酸盐Sm_2Zr_2O_7热导率的影响  

Effect of MgO Doping on the Thermal Conductivity of Sm_2Zr_2O_7

作　　者：瞿志学[1] 万春磊[1] 潘伟[1] 

机构地区：[1]清华大学先进陶瓷与精细工艺国家重点实验室,北京100084

出　　处：《稀有金属材料与工程》2007年第A02期665-667,共3页Rare Metal Materials and Engineering

基　　金：国家自然科学基金项目(50232020;50572042)

摘　　要：通过掺杂二价元素以改变稀土锆酸盐中缺陷浓度的方法,研究了不同含量MgO掺杂对稀土锆酸盐Sm_2Zr_2O_7热扩散系数及热导率的影响。采用高温固相法在1600℃烧结10 h制备得到了致密的试样,所有试样均保持单相的焦绿石结构。结果表明,随着MgO掺杂量的增多,热导率没有降低,反而有升高的趋势:在掺杂量为0.075～0.100范围内有一个斜率的变化,这些变化规律可能与MgO在Sm_2Zr_2O_7中的固溶机理及其变化有关。In order to reduce the thermal conductivity of rare-earth zirconates further, doping method was used to alter the concentration of defects in crystal, and effect of MgO doping on the thermal diffusivity and thermal conductivity of Sm2Zr2O7 was investigated. The samples were prepared by solid state reaction at 1600 ℃ for 10 h in air, and are all single phase with pyrochlore structure. Thermal conductivities of the samples were determined from the data of thermal diffusivity, specific heat capacity and density. The results have shown that the thermal conductivity does not decrease with increasing doping content of MgO as expected, but increase with a change of slope which turns up within the composition range of 0.075-0.100. It may be attributed to the solution mechanism of MgO and its variation.

关 键 词：热障涂层 稀土锆酸盐掺杂 热导率 

分 类 号：O611.3[理学—无机化学]