Crack damage detection by ultra-high frequency A. C. potential method for coated single crystal superalloys

涂层单晶高温合金超高频交流电势法裂纹损伤检测

• 批准号: 12650101
• 负责人: SAKANE Masao
• 金额: $ 2.43万
• 依托单位: Ritsumeikan University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650101/
• 关键词: A. C. potential method; Multiple cracks; Inner defect; Skin effect; Finite element analysis; Damage evaluation; Superalloy; Nondestructive inspection; 交流電位差; 内部欠陥検出; 有限要素法解析; 動電磁場; コーティング; 高温; クリープ疲労; 多軸; 異方性; 寿命評価

This research project investigated two main topics by using A. C. potential method. The both topics are related with the damage assessment of nickel base superalloy gas turbine blades with anti-corrosive and thermal barrier coatings. One was to measure the number of cracks and the crack depth formed on the turbine blade due to thermal stressing. The other was to measure the size and the depth of defects occurred at the interface of the coating and base superalloy.The gradient of the A. C. potential - frequency relationship was deferent depending on the number and the depth of cracks. This means that the number of cracks and the crack depth are determinable by utilizing the frequency dependence of A. C. potentials. The both are actually determinable by comparing the relationships of the target specimen to those in the database where the relationships of many cracked specimens are stored.The maximum value of A. C. potential was corresponded with the size of defects while the gradient of the A. C. potential-frequency relationships reflected the depth of defects. The A. C. potential method was concluded to be capable to measure the size and the depth of defects by measuring the maximum value and the gradient.Harmonic electro-magnetic finite element analyses were carried out to confirm the experimental results obtained. Absolute values obtained in the analyses were not rigorously agreed with the experimental results but the potential ratio normalized by the potential away from the defects agreed well with the experimental results. This clearly indicates that the experimental results obtained in this study had a physical background of electro-magnetic theory.

该研究项目使用A. C.潜在方法研究了两个主要主题。这两个主题均与镍碱基超合金燃气轮机叶片的损坏评估有关，并具有抗腐蚀性和热屏障涂层。一种是测量由于热应力而在涡轮刀片上形成的裂纹数量和裂纹深度。另一个是测量缺陷的大小和深度发生在涂层和基本超合金的界面上。A。C.电位 - 频率关系的梯度取决于裂纹的数量和深度。这意味着可以通过利用A. C.电势的频率依赖性来确定裂纹和裂纹深度的数量。实际上，可以通过将目标标本的关系与存储许多破裂样品关系的数据库中的关系的关系进行比较。 A. C.潜在方法得出结论，能够通过测量最大值和梯度来测量缺陷的大小和深度。进行Harmonic Electro-Magnetic有限元分析以确认获得的实验结果。在分析中获得的绝对值与实验结果并不严格一致，而是由于缺陷的潜力归一化的潜在比率与实验结果一致。这清楚地表明，这项研究中获得的实验结果具有电磁理论的物理背景。

项目成果

Yeonkyeong Lee: "Multiple Surface Crack Detection by A. C. Potential Method"Transactions of the Japan Society of Mechanical Engineers. (accepted). (2001)

Yeonkyeong Lee：“利用交流电位法检测多表面裂纹”日本机械工程师学会会刊。

Yeonkyeong Lee: "Inner Defects Detection by A. C. Potential Method"Proc. 50th Annual Meeting of Japan Science of Materials Science. 379-380 (2001)

Yeonkyeong Lee：“通过交流电势法检测内部缺陷”Proc。

Noritake Hiyoshi: "Tension-Tortion Multiaxial Creep-Fatigue for CMSX-2 Nickel Base Single Crystal Superalloy"Journal of The Society of Materials Science Japan. 50-2. 137-143 (2001)

Noritake Hiyoshi：“CMSX-2 镍基单晶高温合金的拉伸扭转多轴蠕变疲劳”日本材料学会杂志。

李 年慶: "交流電位差法による複数き裂検出法の開発"日本機械学会論文集A編. (投稿中). (2001)

Nianqing Li：“使用交流电位法的多重裂纹检测方法的开发”，日本机械工程学会会刊，A 卷（目前正在提交）（2001 年）。

Yeonkyeong Lee: "Multiple Surface Crack Detection by A. C. Potential Method"Proc. the Committee on High Temperature Strength of Materials, Japan of The Society of Materials Science. 50-4. 3-12 (2002)

Yeonkyeong Lee：“通过交流电势法检测多表面裂纹”Proc。