高温合金GH3039表面ZrO_2-CeO_2/Al_2O_3复合陶瓷涂层抗热震性能  

Thermal shock resistance of ZrO_2-CeO_2/Al_2O_3 composite ceramic coating on superalloy GH3039 by sol-gel method

作　　者：尹春生 姚正军[1,2] 方超 杜文博 YIN Chunsheng;YAO Zhengjun;FANG Chao;DU Wenbo(College of Material Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China;Key Laboratory of Materials Preparation and Protection for Harsh Environment,Ministry of Industry and Information Technology,Nanjing 211106,China)

机构地区：[1]南京航空航天大学材料科学与技术学院,南京211106 [2]面向苛刻环境的材料制备与防护技术工业和信息化部重点实验室,南京211106

出　　处：《复合材料学报》2018年第11期3122-3129,共8页Acta Materiae Compositae Sinica

基　　金：江苏省"六大人才高峰"第十二批高层次人才资助项目(YPC16005-PT);江苏高校优势学科建设工程资助项目;国家自然科学基金(5170010394)

摘　　要：基于溶胶-凝胶技术制备Al_2O_3溶胶及ZrO_2和CeO_2陶瓷粉末,将ZrO_2和CeO_2陶瓷粉末掺杂在Al_2O_3溶胶中形成复合浆料并在高温合金GH3039表面分别制备Al_2O_3、ZrO_2/Al_2O_3和ZrO_2-CeO_2/Al_2O_3复合陶瓷涂层,通过XRD、SEM、EDS、DSC等检测手段研究不同陶瓷粉末的加入对复合陶瓷涂层在900℃抗热震性能的影响。结果表明:未添加任何陶瓷粉末的纯Al_2O_3陶瓷涂层在烧结过程中会产生大量的宏观裂纹,涂层表面质量差且易剥落;在Al_2O_3溶胶中掺杂ZrO_2陶瓷粉末后,ZrO_2/Al_2O_3复合陶瓷涂层的结构致密无明显宏观裂纹且涂层与基体的附着力明显增加;当掺杂粉末为CeO_2∶ZrO_2=1∶10(摩尔比)时,CeO_2可稳定高温下易发生相变的ZrO_2,阻止其由t-ZrO_2向m-ZrO_2的转变,陶瓷颗粒在Al_2O_3网络膜中分散均匀并呈现出纳米Al_2O_3颗粒包覆ZrO_2-CeO_2大颗粒的结构,这种结构使ZrO_2-CeO_2/Al_2O_3涂层的抗热震性能和抗剥落较ZrO_2/Al_2O_3复合陶瓷涂层更优异。ZrO_2-CeO_2/Al_2O_3复合陶瓷涂层能够缓解纯Al_2O_3陶瓷涂层与基体之间热膨胀系数不匹配而造成易剥落的问题,从而延长了涂层寿命,进一步提高基体的抗热震性能。Preparation of Al2O3 sol and ZrO2 and CeO2 ceramic powder based on sol-gel method were prepared.The ceramic powders were dispersed in Al2O3 sol to form the composite slurry,then ZrO2/Al2O3 and ZrO2-CeO2/Al2O3 composite ceramic coatings were prepared on the surface of superalloy GH3039 substrate by XRD,SEM,EDS and DSC to study the influence of different ceramic powder on thermal shock resistance of composite sol-gel coating at 900℃.The results indicate that the pure Al2O3 coating without any ceramic powder has a large number of macro crack,bad surface integrity and easy peeling during the process of sintering;when the ZrO2 ceramic powder is added into the Al2O3 sol,the structure of the ZrO2/Al2O3 composite ceramic coating has no obvious macro crack and the adhesion between the coating and the substrate increases significantly;when CeO2∶ZrO2=1∶10（molar ratio）,CeO2 can stabilize the phase transition under high temperature,which can prevent the transition from t-ZrO2 to mZrO2.The ceramic particles are dispersed homogeneously in the Al2O3 network film and present the structure ofcoated ZrO2-CeO2 particles covered with nano Al2O3 particles.This structure makes the thermal shock resistance and spalling resistance of Al2O3 composite ceramic coating more excellent than the ZrO2/Al2O3 composite ceramic coating.ZrO2-CeO2/Al2O3 composite ceramic coatings can solve the thermal coefficient mismatch problem between matrix and Al2O3 coating so as to further improve the performance of matrix thermal shock and prolongs lifetime of the superalloy GH3039.

关 键 词：溶胶-凝胶 高温合金 纳米粉末 复合陶瓷涂层 抗热震性 

分 类 号：TG174.45[金属学及工艺—金属表面处理]