Laser Ultrasonic Non-Destructive Testing for Aerospace Applications

Non destructive inspection (NDI) is a widely used method for quality control and materials inspection across various industries, especially in the aerospace field where the introduction of composite materials has revolutionized inspection techniques. In addition, in-service ultrasonic inspection (UT) is also used for preventive maintenance purposes. One of the biggest challenges of such techniques is the need to use a coupling medium, which can often be a critical issue. For this reason, considerable effort has been made in the aerospace field in recent years to employ innovative techniques that do not require the use of coupling media. One of the proposed techniques is Laser Ultrasonic Non-Destructive Testing (LUNDT), which is recognized as a promising method due to its rapid scanning speed, non-contact inspection, coupling-agent independence, and ability to inspect complex shapes. Today, the primary focus is not on generating ultrasound in the material, but rather on how to receive and interpret it. In recent years, several companies have attempted to provide their own solutions in this field. In this study, the utilized solution is based on an all-optical akinetic sensor, which has demonstrated the most promising results. With this technology, we performed a series of analyses on aerospace components of interest, including those made of composite and metallic materials.