ABSTRACT The manufacturing of Fibre Metal Laminates, consisting of alternating layers of pre-preg fibre and metal is complex, and defects can be introduced during manufacturing. The automation of the manufacturing steps is vital for future Glare production, and specific defects have to be considered. Among them, gaps between pre-preg plies represent a potential risk for the mechanical performances of the laminate. In this paper/research, non-destructive testing based on ultrasonic inspections are performed on Glare with pre-preg gaps in order to extend and improve the current state of the art to different pre-preg gap widths, depths, and lay-ups. Firstly, gaps were introduced in Glare specimens. Then, a conventional C-scan ultrasonic inspection is performed. In order to overcome the current limitations of a top or planar view of the laminates, the evaluation of the depth of the gaps in the laminates is performed by means of phased array ultrasonic testing. Finally, images of the laminate cross-section have been collected in order to provide a meaningful evidence of the ultrasonic-based analysis. Results from different Glare and gap widths and depths show the accuracy of the proposed investigation which is able to provide a detailed assessment of the gap occurrences also for very thin laminates.

中文翻译：

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薄Glare层压板间隙的无损检测研究

摘要 由预浸纤维和金属交替层组成的纤维金属层压板的制造很复杂，并且在制造过程中会引入缺陷。制造步骤的自动化对于未来的 Glare 生产至关重要，必须考虑特定的缺陷。其中，预浸料层之间的间隙代表了层压板机械性能的潜在风险。在本文/研究中，对具有预浸料间隙的眩光进行了基于超声波检测的无损检测，以将现有技术扩展和改进到不同的预浸料间隙宽度、深度和叠层。首先，在眩光样品中引入了间隙。然后，执行传统的 C 扫描超声检查。为了克服层压板的俯视图或平面图的当前限制，层压板间隙深度的评估是通过相控阵超声波测试进行的。最后，收集了层压板横截面的图像，以便为基于超声波的分析提供有意义的证据。来自不同眩光和间隙宽度和深度的结果显示了所提议调查的准确性，这也能够为非常薄的层压板提供间隙发生的详细评估。