Thermal Shock Fracture Mechanism of Thermal Barrier Coatings for Gas Turbine Blades

燃气轮机叶片热障涂层热冲击断裂机理

• 批准号: 08455314
• 负责人: KAWASAKI Akira
• 金额: $ 1.6万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08455314/
• 关键词: ceramic coating; plasma spray process; gas turbine blade; thermal resistance; thermal shock; thermal fatigue; spalltion fracture; acoustic emission; ガスタービンブレ-ド

In high temperature components of gas turbine engines which include combustor liners, turbine blades and after-burners, thermal barrier coatings (TBCs) are being employed for improved performance, efficiency and extended component life by reducing turbine cooling air while keeping sufficiently low metal temperatures.The major problem in thermal barrier coatings applied to gas turbine components is the spallation of ceramic coating under thermal cycling environments. In order to study the spalling behavior and durability of functionally graded thermal barrier coatings, the well controlled burner-heating-test-method has been developed and evaluation process of number of cycles to spall has been proposed.In this research the cyclic thermal fracture behavior and the evaluation of spallation life of PSZ/NiCrAlY functionally graded thermal barrier coatings has been investigated. Three types of FGM coating and conventional duplex coating were fabricated to demonstrate the marked advantages of … More functionally graded structure on the improvement of spallation life of the TBCs under cyclic thermal loads. The effect of compositional profile in the FGM coatings on spallation life has been discussed.The sequence of spalling behavior has been found to be ; orthogonal crack formation on the top surface during cooling, then transverse crack formation in the graded layer during heating, and subsequent growth of transverse cracks and their coalescence which leads eventually the ceramic coat to spall. It is shown that the spallation life of the coating can be defined as the critical number of thermal cycle, evaluated from either the rapid increase of AE hits during heating or the sudden drop of the effective thermal conductivity. Comparing with duplex coatings, it has been revealed that functionally graded TBCs possess the desirable effect for improvement of spallation life under cyclic thermal loads. In addition, the dependence of spallation life on the composition profile in functionally graded coatings has been shown. Less

在燃气涡轮机发动机的高温部件（包括燃烧室衬套、涡轮机叶片和加力燃烧室）中，热障涂层（TBCs）通过减少涡轮机冷却空气而保持足够低的金属温度来提高性能、效率和延长部件寿命。热障涂层应用于燃气涡轮机部件的主要问题是陶瓷涂层在热循环环境下的剥落。为了研究功能梯度热障涂层的剥落行为和耐久性，建立了可控燃烧器加热试验方法和剥落循环次数评价方法，研究了PSZ/NiCrAlY功能梯度热障涂层的循环热断裂行为和剥落寿命评价。制备了三种类型的FGM涂层和传统的双层涂层，以证明FGM涂层的显著优点。 ...更多信息 功能梯度结构对提高循环热载荷下热障涂层寿命的影响。讨论了梯度功能陶瓷涂层的成分分布对剥落寿命的影响，发现剥落行为的顺序是：冷却时在梯度层上形成正交裂纹，加热时在梯度层上形成横向裂纹，随后横向裂纹扩展并合并，最终导致陶瓷涂层剥落。结果表明，涂层的寿命可以定义为临界热循环次数，从加热过程中的AE命中的快速增加或有效热导率的突然下降来评估。与双层涂层相比，功能梯度涂层对提高循环热载荷下热障涂层的寿命具有良好的效果。此外，在功能梯度涂层的组成分布的溅射寿命的依赖性已被证明。少

项目成果

A.Kawasaki: "Fracture Behavior of PSZ/SS Thermal Barrier Coatings Studied by Cyclic Burner Heating Test" vol.44, No.8. 734-739 (1997)

A.Kawasaki：“通过循环燃烧器加热试验研究的 PSZ/SS 热障涂层的断裂行为”第 44 卷，第 8 期。

川崎 亮: "Cyclic thermal fracture behavior and spallation life of PSZ/NiCrAlY functionally graded thermal barrier coatings" Proceedings of 5th International Symposium on Functionally Graded Materials, FGM '98, Oct.26-29, 1998, (Dresden, Germany). in press.

Ryo Kawasaki：“PSZ/NiCrAlY 功能梯度热障涂层的循环热断裂行为和剥落寿命”第五届功能梯度材料国际研讨会论文集，FGM 98，1998 年 10 月 26-29 日，（德国德累斯顿）。按。

川崎 亮: "PSZ/ステンレス鋼系遮熱コーティングの熱サイクル破壊挙動" 粉体および粉末冶金. 44.8. 734-739 (1997)

Ryo Kawasaki：“PSZ/不锈钢热障涂层的热循环失效行为”粉末和粉末冶金 734-739 (1997)。

A.Kawasaki: "Cyclic thermal fracture behavior and spallation life of PSZ/NiCrAlY functionally graded thermal barrier coating" Proc.of 5th Int.Symp.on Functionally Graded Materials, FGM '98, Oct.26-29 (Dresden, Germany). (in press). (1998)

A.Kawasaki：“PSZ/NiCrAlY 功能梯度热障涂层的循环热断裂行为和剥落寿命”Proc.of 5th Int.Symp.on 功能梯度材料，FGM 98，10 月 26-29 日（德国德累斯顿）。