采用超音速火焰喷涂在航空发动机热端部件DZ40M合金表面制备了铝含量不同(6％、8％和12％)的Ni-Co基粘结层,再等离子喷涂YSZ(氧化钇稳定氧化锆)陶瓷面层,制得了热障涂层.通过扫描电镜、X射线衍射仪和拉曼光谱仪研究了粘结层成分及其真空热处理对热障涂层显微形貌、物相组成以及界面热生长氧化物(TGO)的影响.结果表明,3种粘结层的致密性均较高,与基材以及陶瓷层结合较好.3种喷涂态粘结层中的物相组成与原始粉末相似,随着A1含量增加,原始粉末和喷涂态粘结层中β相的含量逐渐增加.粘结层的真空热处理可以有效降低3种热障涂层在静态氧化过程中TGO的增厚速率.未经粘结层真空热处理制成的热障涂层中,TGO的增速与粘结层中A1的含量有关.粘结层真空热处理后,晶界扩散会显著影响TGO的增厚速率,TGO晶粒尺寸的增加会造成晶界数量减少,相应地会降低TGO的增厚速率.%Ni-Co-based bonding layers with different Al contents (6％,8％ and 12％) were prepared on the surface of DZ40M alloy for hot section component of aeroengine by supersonic flame spraying,and then covered with YSZ (yttriastabilized zirconia) ceramic layers by plasma spraying,forming thermal barrier coatings.The effects of the composition and vacuum heat treatment of bonding layer on the micromorphology,phase composition and thermally grown oxide (TGO) of thermal barrier coating were studied by scanning electron microscope,X-ray diffractometer and Raman spectrometer.The results showed that all the three kinds of bonding layers are compact and well bonded with the substrate and the ceramic layer.The phase compositions of all the as-sprayed bonding layers are similar to the original powders.The contents of beta phase in the as-sprayed bonding layer and in the original powder are gradually increased with the increasing of A1 content.Vacuum heat treatment for bonding layer effectively reduces the TGO thickening speed of all the thermal barrier coatings in a static oxidation process.The growth of TGO is related to the content of A1 in bonding layer for the thermal barrier coating prepared without vacuum heat treatment of bonding layer.The diffusion at grain boundaries significantly affects the thickening speed of TGO in the thermal barrier coating prepared with vacuum heat treatment of bonding layer.The grain boundaries are reduced with the increasing of the grain size of TGO,resulting in a decrease of TGO thickening speed.
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