改性ZrO2新型热障涂层材料的相稳定机制及相变动力学研究

项目名称： 改性ZrO2新型热障涂层材料的相稳定机制及相变动力学研究

项目编号： No.51202295

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 无机非金属材料学科

项目作者： 刘怀菲

作者单位： 中南大学

项目金额： 23万元

中文摘要： 传统6-8wt.%氧化钇稳定氧化锆热障涂层（YSZ-TBC）在高于1200℃长期应用时存在严重热稳定性（相变）问题，成为高性能航空发动机热端部件材料必须克服的技术瓶颈。针对该材料体系的局限性，多元稀土氧化物稳定氧化锆新型陶瓷材料的制备已成为国内外热障涂层研究的热点,但稀土氧化物稳定氧化锆的改性设计，特别是相稳定机制及高温相变动力学行为，一直缺乏充分认识和理论支持。本项目以RE3+（RE=La, Yb, Sc）、Y3+共稳定氧化锆新型热障涂层为研究对象，通过开展相图计算、相结构测定及晶体结构精细解析，建立掺杂元素特征（原子量、离子半径）、晶体结构、相稳定性之间的相关性。分析改性体系表面电子及原子价键结构，揭示稀土氧化物掺杂稳定机制。深入研究改性体系的高温相变动力学行为，探明相变机制及相变关键因素。本项目研究将为新型高温热障涂层材料的选择、成分设计、性能评估和寿命预测提供理论依据和科学指导。

中文关键词： 热障涂层；稀土氧化物；相稳定性；相变动力学；氧化锆

英文摘要： For long time service over 1200℃, the traditional YSZ-TBC has a serious thermal stability(phase transformation)problem, which is the key technology to be conquered for its application as hot components material of high performance aircraft engine. To overcome this limitation, the development and production of ZrO2 codoped by multivariate rare earth oxides thermal barrier coating has become a research hot issue on TBCs. However, the modification of ZrO2 codoped by multivariate rare earth oxides thermal barrier coating, especially the phase stability mechanism and phase transformation kinetic at high temperature, is not fully understood both experimentally and theoretically. In the present project, researched are doing with RE3+（RE=La, Yb, Sc）、Y3+ co-stabilized zirconia novel thermal barrier coatings as research objects: Phase diagram calculation, structure anticipation and detailed analysis of crystals are presented to establish the relationship among the codoped elements (atomic mass, ionic radius) and crystal structure as well as phase stability; The phase stability mechanisms of REYSZ systems are revealed via the analysis of surface electronic and valence bond structure. Phase transformation kinetic behaviors of the modified systems are studied. Phase transformation mechanisms and key phase transformation fac

英文关键词： thermal barrier coating；rare earth oxide；phase stability；phase transformation kinetics；zirconia