Scanning of the internal structure part with laser ultrasonic in aviation industry

Abstract

The detection of internal defects is a major production and safety issue for the newest generations of aircraft. New materials and manufacturing processes in the aircraft industry demand efficient quality assurance in manufacturing and inspection in maintenance. Advanced metallic material processes (titanium) are used or developed for the production of heavily loaded flying components (in fan blade construction). The inspection of these parts mainly made out of titanium (or CFRP) requires the determination of the percentage of bonded grain sizes around 10-30 µm. This is primarily due to the advantages of a high signal-to-noise ratio and good detection sensitivity. In this article, a diagnosing method of the blade interior by means of the laser ultrasonic is presented. Identification of small fatigue cracks presents a challenging problem during nondestructive testing of fatigue-damaged structures. Laser ultrasonic is a technique that uses two laser beams; one with a short pulse for the generation of ultrasound and another with a long pulse or continuous coupled to an optical interferometer for detection. The results of research of the internal blade structure are presented.

The use of nondestructive evaluation methods in fatigue: A review

“…[98][99][100]105 Additionally, AE data trends have been recently investigated as a potential tool to inform physics-based models of the damage degradation which allows for improved data-driven fatigue life predictions. 112 While the passive AE method is commonly used for fatigue monitoring in situ, the active UT method can be used to interrogate the existing damage without the need for further external loading and mostly to determine crack size 113,114 and location inside the material. 113 Figure 12 includes a representative example in which damage maps were obtained by the so-called C-scans to determine the initial distribution of defects (in this case delaminations) and compared it with subsequent damage.…”

“…While the passive AE method is commonly used for fatigue monitoring in situ, the active UT method can be used to interrogate the existing damage without the need for further external loading and mostly to determine crack size and location inside the material . Figure includes a representative example in which damage maps were obtained by the so‐called C‐scans to determine the initial distribution of defects (in this case delaminations) and compared it with subsequent damage .…”

Overview of monitoring methods of press‐pack insulated gate bipolar transistor modules under different package failure modes

“…In the other solution, ultrasonic technology is used for pressure measurement. Ultrasonic technology has been widely used in defect detection [70], bolt stress detection [71], and contact surface detection [72]. In bounded elastic solids, the propagation of ultrasonic waves often interacts with the boundary in the form of reflection and refraction.…”

High‐Speed Scanning of Critical Structures in Aviation Using Coordinate Measurement Machine and the Laser Ultrasonic

“…For the evaluation of defects such as cracks and corrosion, the X‐ray is a good method but the measurement depth is low (only 5–10 μm) (Ting et al., ). Measurement is slow, requires access to both sides of the structure, harmful radiation, low contrast for cracks, and very expensive equipment.The YAG (Yttrium Aluminium Garnet) laser ultrasonic method combined with a laser is a noncontact and nondestructive method that can be applied on surfaces with complicated forms (Pétillon et al., ; Schmerr and Song, ; Swornowski, ). The YAG laser ultrasonic is used for identification of defects like corrosion or cracks with little limitations.…”