CeO2/ZrO2-Y2O3纳米结构热障涂层的制备与高温性能

Preparation and High-temperature Properties of Nanostructured CeO_2/ZrO_2-Y_2O_3 Thermal Barrier Coating

将纳米ZrO_2-8wt%Y_2O_3和纳米ZrO_2-8wt%Y_2O_3中掺杂25wt%纳米CeO_2(CeO_2/ZrO_2-8wt%Y_2O_3)的两种粉末进行团聚处理,用等离子喷涂方法在GH30高温合金表面分别制备了两种材料热障涂层.用扫描电镜、透射电镜和X射线衍射仪对掺杂了25wt%纳米CeO_2的团聚体粉末和涂层的微观组织结构进行分析研究,测试比较了两种涂层在900、1100和1300℃时的热震性能,并试验了两种涂层在1050℃、保温100h后的抗氧化能力.结果表明,纳米粉末经团聚处理后为多孔的球形结构,掺杂纳米CeO_2涂层组成相为稳定的t相(t-ZrO_2、t-Zr_(0.82)Y_(0.18)O_(1.91)、t-Zr_(0.82)Ce_(0.18)O_2)和c相(c-CeO_2),并保持纳米组织结构,平均晶粒尺寸为45nm,其抗热震性能和氧化性能要高于纳米ZrO_2-8wt%Y_2O_3涂层.

The nanosized ZrO_2-8wt%Y_2O_3（YSZ） and CeO_2/ZrO_2-8wt%Y_2O_3（CYZ） particles were agglomerated as powder feedstocks.Thermal barrier coatings were prepared on the GH30 high temperature alloy surface by atmospheric plasma spray.The microstructures of the agglomerated powders doped with 25wt%CeO_2 particles and the coating were characterized using scanning electron microscope（SEM）,transmission electron microscope（TEM） and X-ray diffraction（XRD） technology.The thermal shocks resistance of the ZrO_2-8wt%Y_2O_3（YSZ） and CeO_2/ZrO_2-8wt%Y_2O_3（CYZ） coatings were tested at 900℃,1100℃and 1300℃.The oxidation resistance testing of coatings were tested at 1050℃for 100h.The results show that the nano-powder by agglomerated treatment is porous spherical.The phase compositons of the nano-CYZ coating are relatively stable t phase（t-ZrO_2, t-Zr_（0.82）Y_（0.81）O_（1.91）,t-Zr_（0.82）Ce_（0.18）O_2） and c phase（c-CeO_2）.The average grain size of the CYZ coating is about 45nm. The nanostnictured CeO_2/ZrO_2-Y_2O_3 coating exhibit higher thermal-shock and oxidation resistances than those of the nano-YSZ coating.