Why Eddy Current Testing of Aluminum Plates Matters in the Aerospace Industry

The inspection of aluminum plates calls for a nondestructive testing (NDT) method that can probe through multiple layers and thick welding. The ideal technique is eddy current testing (ECT), which is best suited for the testing of thin materials like aluminum plates. However, technicians need an augmented ECT regimen that can adapt to aerospace materials.

Eddy current array (ECA) is one of the best options because the probes can adapt to the contours of aluminum plating, helping technicians obtain reliable data. Additionally, ECA probing provides customization schemes that save time during the testing process. This article will explain why eddy current testing of aluminum is best done with eddy current array technology. 

What to Look for in an Instrument for Aluminum Plate Inspection 

A key element for powerful probing of an aluminum plate is the instrumentation. To get the best results, choose an ECT instrument from a reliable NDT provider that invests in cutting-edge signal quality. A quality signal-to-noise ratio can help users detect material losses within aluminum plating, especially in multilayered plates that can obscure signal quality. The dual-frequency aspect also eradicates air gaps between layers that can distort signal prowess. 

An instrument should also have handheld portability that offers greater mobility and reduced inspection times. Technicians can also avoid excessive arm fatigue that could hamper the testing process and cause inaccurate probe findings. Other NDT methods like magnetic particle testing (MPT) fail to provide the same level of portability, as MPT instruments typically require an ever-present electrical source to function. An ECT instrument functions without electrical inputs and can power up to twice as long compared to some other instruments. 

Overall, the best ECT devices should come with the following set of universal benefits:

• A superior magnification schematic that scrutinizes all detected flaws.
• Long battery life that eliminates the need for outlets and frequent battery changes.
• Intuitive user interface, which leads to an inherently higher probability of detection and reduces the amount and frequency of training required
• Compatibility with a wide range of probes and scanners, including flexible probes that enable technicians to reach challenging or hard-to-reach areas
• Dual frequency mixing that dispels unnecessary signals

These additions help operators find more deviations during the inspection campaign, including hard-to-reach areas that are harder to inspect with other instruments. A good ECT instrument can comb through an aluminum plate with ease and inspect multi-layer plating without additional hardware or software.

Eddy Current Evolution with Array Technology 

When paired with array probes, analysts can obtain a more resolute depiction of aluminum plates and multi-layer structures. The array addition strengthens the probability of detection, an added benefit for plates with fastener holes, including ones with additional layers. And the low-frequency and versatile probing can make the testing of thicker, aluminum plates easier. 

Array probing can simplify the inspection of aluminum plates in the following ways:

• Efficient setup capabilities that save time. 
• Multi-coil add-ons that can better adapt to varying shapes and sizes.
• Superior position indicators that enhance the alignment process and reduce frequent probe adjustments.

The array add-on can detect all forms of deviations—such as cracking, corrosion, or pitting—with interchangeable probes. Array probes are detail-oriented enough to detect infinitesimal cracking on plates with minimal passes. Users can also cover wider areas with a single pass of the probe and obtain comprehensive data in a shorter timespan. 

The array functionality also means faster inspection times. With ECA techniques, users can reduce inspection sessions by as much as 95 percent compared to ordinary ECT practices like pencil probing. Users can save money in the long-term by shortening inspection intervals, giving technicians more time to focus on flaw detection and extracting hidden deviations that could compromise weld integrity. 

Using ECA for Ultrasonic Inspection of Aluminum Plate 

ECT is a powerful NDT method for aluminum plates, but it needs array support to pinpoint flaws in greater detail and to conform to complex surfaces. An ECA instrument with state-of-the-art signal quality can detect material loss while probing through thick plates without fail. 

Eddy current testing of aluminum with array support can also help users find small cracks and other aberrations that are harder to detect with other NDT techniques like MPT. With interchangeable coil sets and prime indicators, technicians can cover more testing ground in a shorter time frame. ECA probes can detect just about all types of flaws on aluminum plates, giving maintenance departments more time to formulate precise maintenance strategies. 

Zetec is a top provider of ECT equipment and ECA probes, both of which enhance the testing process on aluminum plating and multi-layered welding structures. Contact us today to learn about the best instruments for your NDT needs.