Mistras Group
Futureproof Your Composite Structure Inspections with Time Reversal Technique
Posted:
By: Eddyfi Technologies
Source: Eddyfi Technologies
With the evolution in composite material technologies, aircraft composition has shifted with the commercial aircraft industry incorporating increasingly more composite materials such as CFRP in their structures. And no wonder with CFRP components offering the advantages of being lightweight yet robust. These composite structures are typically shaped in complex and variable geometries. And that’s where the challenge for NDT inspection of CFRP components comes in.

The preferred NDT technology for complex composites inspection is phased array ultrasonic testing (PAUT). A combination of dedicated probe configurations, a high-performance PAUT system, and advanced software that includes specific tools and algorithms is necessary for fast and reliable inspections. Standard phased array UT inspection requires precise alignment between the probe and the specimen. In the case of complex geometries, this typically involves comprehensive and therefore expensive systems, and precise knowledge of the specimen geometry. Recently, the Time Reversal technique —a real-time adaptive process— has been implemented for rapid and reliable phased array UT inspections on these complex geometries.

Here's the problem

Composite structures are being used more and more in aircraft. This includes the fuselage and different parts of the wings, the skin, stringers, and spars. All these components have different shapes, most of which are complex geometries. Therefore, the examination method must be adaptable to these challenging conditions.

The manufacturing process of composite materials can create different types of defects. Inspection after manufacturing must be able to detect porosities, foreign bodies, and delamination present in the CFRP structures (Figure 2). Another challenging aspect of the examination of aerospace components is inspection speed. The large manufacturing volumes demand high inspection speed in order to reduce cost.

Read the full blog article at Eddyfi.com.

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