Fatigue Strength of Functionally Graded Thermal Barrier Ceramic Coatings Subjected to Thermal Cycling under Gradient Temperature

梯度温度下热循环功能梯度热障陶瓷涂层的疲劳强度

基本信息

批准号：
06452147
负责人：
MUTOH Yoshiharu
金额：
$ 4.86万
依托单位：
Nagaoka University of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1996
项目状态：
已结题

项目摘要

Surface modification techniques, such as thermal barrier coatings and protective coatings are key technology to develop next generation advanced gas turbines. As a part of program to develop the high performance coating systems for advanced gas turbines, the high temperature strength of the advanced materials with surface modifications has been studied in this research program. The conclusions obtained are summarized as follows :(1) A new fatigue test machine which can simulate the service condition of turbine blades and vanes was successfully produced.(2) Thermal fatigue tests of conventional two-layr NFGM coating specimens and a functionally gradient material (FGM) coating specimens were carried out. Damage process of the functionally graded thermal barrier coatings during the thermal cycling was qualified. The degradation of thermal barrier function of the FGM was also qualified.(3) The effect of the functionally graded thermal barrier coatings on the thermal fatigue strength of the … More advanced materials with ceramic coatings surface damage strength was quantitatively evaluated by the thermal cycling test in vacuum.(4) The fatigue fracture of the Ni-base superalloy, IN 738LC,coated with the so-called M-Cr-Al-Y alloys by low pressure plasma spraying was studied and clarified at high temperature in vacuum condition, compared with that of the substrate alloy, IN 738LC.The fatigue crack propagation process was also made clear from the investigation employing the special equipment with cyclic loading stages which fit within the scanning electron microscope. Special focus was paod on the fatigue crack growth behavior in the coated layr and the dependence of the MCrAlY alloy systems, as well as near the interface.(5) The effect of aluminide coating on the high-cycle fatigue strengths of Ni-base superalloys was clarified at room temperature and 800 ﾟC in vacuum, in comparison with those of the substrates. Based on the measurement of a critical strain above which brittle cracking appeared at the aluminide coating, a simple method which can provide a reasonable estimation corresponding with the experimental life, was proposed. Less

在此研究计划中，已研究表面修饰的表面修饰技术。叶片成功产生通过在738LC中的热循环测试评估损伤强度的热疲劳强度上的热屏障涂层的数量。与底物合金相比，在738LC中，真空中的温度也从具有循环载荷阶段的特殊设备中明确了疲劳裂纹的繁殖过程，这些设备适合扫描电子显微镜。与底托相比，涂层的LAR和MCRALY系统界面是较少的