氧化镁和氧化铈复合部分稳定氧化锆泡沫陶瓷的显微结构

MICROSTRUCTURE OF PARTIALLY STABILIZED ZIRCONIA FOAM CERAMIC WITH MgO AND CeO_2

分别以纯ZrO2,97%(质量分数,下同)ZrO2+3%MgO,96%ZrO2+3%MgO+1%富铈稀土3种成分制得3组泡沫陶瓷样品,以钢液浇注实验评价高温性能。用X射线衍射仪分析相组成。用环境扫描电镜和能谱分析仪观察陶瓷的显微结构。结果表明:96%ZrO2+3%MgO+1%富铈稀土复合部分稳定ZrO2具有很好的高温性能。稳定剂不但可部分稳定形成一定量四方相与立方相的ZrO2,而且对ZrO2泡沫陶瓷烧结起促进作用。这是由于CeO2中Ce4+半径更接近Zr4+,CeO2在ZrO2中有较大固溶度,因而对ZrO2的稳定与烧结传质起到更强的促进作用。

Three groups of foam ceramic samples were prepared with different components of pure ZrO2, 97% （in mass, the same below） ZrO2＋3%MgO and 96% ZrO2＋3%MgO＋1% rich cerium rare earth as raw materials. The high-temperature properties of the foam ceramic samples were estimated by practical casting. The phase composition was analyzed by X-ray diffraction, and the microstructure was observed by environment scanning electron microscope. The results indicate that partial stability zircon （PSZ） with the composition of 96% ZrO2＋3%MgO＋1% rich cerinm rare earth has the best high-temperature performance. The stabilizers can partially stabilize the cubic phase and tetragonal phase of ZrO2 as well as promote the sintering of ZrO2 foam ceramic. Because the radius of Ce^4＋ in CeO2 is closer to that of Zr^4＋, the CeO2 has more solid solubility in ZrO2, and thus can better promote the stabilization of ZrO2and the mass-transfer in the process of sintering.