Mohseni Ehsan, Habibzadeh Boukani Hamid, Ramos França Demartonne, Viens Martin
1Center for Ultrasonic Engineering (CUE), Department of Electronics and Electrical Engineering, Technology and Innovation Centre, University of Strathclyde, 99 George Street, Glasgow, G1 1RD UK.
Département de génie mécanique, L'École de technologie supérieure, 1100 Rue Notre-Dame O, Montréal, QC H3C 1 K3 Canada.
J Nondestr Eval. 2020;39(1):6. doi: 10.1007/s10921-019-0647-9. Epub 2019 Dec 28.
Applying life estimation approaches to determine in-service life of structures and plan the inspection schedules accordingly are becoming acceptable safety design procedures in aerospace. However, these design systems shall be fed with reliable parameters related to material properties, loading conditions and defect characteristics. In this context, the role of non-destructive (NDT) testing reliability is of high importance in detecting and sizing defects. Eddy current test (ECT) is an electromagnetic NDT method frequently used to inspect tiny surface fatigue cracks in sensitive industries. Owing to the new advances in robotic technologies, there is a trend to integrate the ECT into automated systems to perform NDT inspections more efficiently. In fact, ECT can be effectively automated as to increase the coverage, repeatability and scanning speed. The reliability of ECT scanning, however, should be thoroughly investigated and compared to conventional modes of applications to obtain a better understanding of the advantages and shortcomings related to this technique. In this contribution, a series of manual and automated ECT tests are carried out on a set of samples using a split-D reflection differential surface probe. The study investigates the level of noise recorded in each technique and discuss its dependency on different parameters, such as surface roughness and frequency. Afterwards, a description of the effect of crack orientation on ECT signal amplitude is provided through experimental tests and finite element simulations. Finally, the reliability of each ECT technique is investigated by means of probability of detection (POD) curves. POD parameters are then extracted and compared to examine the effect of scanning index, frequency and automation on detection reliability.
应用寿命估算方法来确定结构的服役寿命并据此规划检查计划，正成为航空航天领域可接受的安全设计程序。然而，这些设计系统需要输入与材料特性、载荷条件和缺陷特征相关的可靠参数。在此背景下，无损检测（NDT）可靠性在检测和测量缺陷方面起着至关重要的作用。涡流检测（ECT）是一种电磁无损检测方法，常用于敏感行业检测微小的表面疲劳裂纹。由于机器人技术的新进展，有一种将ECT集成到自动化系统中以更高效地进行无损检测的趋势。事实上，ECT可以有效地实现自动化，以提高检测覆盖率、重复性和扫描速度。然而，ECT扫描的可靠性应进行深入研究，并与传统应用模式进行比较，以便更好地了解该技术的优缺点。在本论文中，使用分裂D反射差分表面探头对一组样品进行了一系列手动和自动ECT测试。该研究调查了每种技术中记录的噪声水平，并讨论了其对不同参数（如表面粗糙度和频率）的依赖性。之后，通过实验测试和有限元模拟，描述了裂纹取向对ECT信号幅度的影响。最后，通过检测概率（POD）曲线研究了每种ECT技术的可靠性。然后提取POD参数并进行比较，以检验扫描指数、频率和自动化对检测可靠性的影响。
