权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Development of Thermographic NDTTechnique Based on Lock-in Measurement of Thermal Wave Response for Structural Integrity Assessment of Aging Aircraft

基于热波响应锁定测量的热成像无损检测技术的发展，用于老化飞机的结构完整性评估

基本信息

批准号：
12555027
负责人：
SAKAGAMI Takahide
金额：
$ 8.26万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

项目摘要

The present project developed a new quantitative nondestructive testing (NDT) technique for structural integrity assessment of aging aircrafts. The results obtained are summarized as follows.1. For detecting cracks, singular electrothermal field near crack tips under the application of periodically modulated electric current was measured using lock-in thermography. Experimental investigations were made on the resolution and the applicability in the identification of cracks embedded in steel and aluminum alloy plates. Significant singular electrothermal field was observed at the crack tip in die lock-in thermal image. Location and size of the crack were accurately determined, demonstrating the feasibility of the proposed technique.2. For material loss defects and delamination defects, a thermographic NDT technique based on the lock-in measurement of the surface temperature under periodical heating was developed. Experimental study was made on the applicability to the detection of flat b … More ottom hole defects and delamination defects. In-phase and out-of-phase temperature amplitude images were taken by the lock-in thermography, synchronized to the reference signal of the periodical heating. Further, another thermographic NDT technique based on the transient temperature under the pulse heating was developed. Temperature descent curve which reflects defect parameters such as size, shape and depth of defects was analyzed using Fourier series. Developed techniques were applied to the identification of material loss defects and delamination defects in aerospace structures. It was found that defect parameters can be accurately determined by the developed thermographic NDT techniques.3. Quantitative NDT technique for delamination defects in concrete structures was developed based on the phase delay measurement using a lock-in infrared thermography. Location and size of the defect can be estimated from the contrast change and depth can be estimated from the relationship between phase delay and heating period.4. Passive electric potential CT method was developed as a new monitoring technique. Electric potential distribution measurement on the surface of piezoelectric film glued on the structure was processed by inverse analysis. Less

本项目开发了一种新的定量无损检测(NDT)技术，用于老化飞机的结构完整性评估。所获得的结果概括如下：1.为了检测裂纹，利用锁定热像仪测量了周期性调制电流作用下裂纹尖端附近的奇异电热场。对裂纹的分辨率及其在钢板和铝合金板裂纹识别中的适用性进行了实验研究。在锁模热像中，在裂纹尖端观察到明显的奇异电热场。准确地确定了裂纹的位置和大小，证明了所提技术的可行性。针对材料损耗缺陷和分层缺陷，发展了一种基于周期性加热下锁定测量表面温度的热像无损检测技术。对平坦b…检测的适用性进行了实验研究。较多的孔洞缺陷和分层缺陷。利用锁相式热像仪拍摄了同相和异相温度幅值图像，并与周期性加热的参考信号同步。在此基础上，发展了另一种基于脉冲加热下的瞬时温度的热像无损检测技术。利用傅里叶级数分析了反映缺陷尺寸、形状和深度等缺陷参数的温降曲线。将所开发的技术应用于航天结构中材料损失缺陷和分层缺陷的识别。结果表明，所开发的热像无损检测技术可以准确地确定缺陷参数。基于锁相式红外热像仪的相位延迟测量，发展了混凝土结构分层缺陷的定量无损检测技术。根据对比度的变化可以估计缺陷的位置和大小，根据相位延迟与加热周期的关系可以估计缺陷的深度。被动电位CT法是近年来发展起来的一种新的监测技术。对粘贴在结构上的压电膜表面的电势分布进行了反分析。较少