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Nondestructive Testing (NDT)

Nondestructive Testing (NDT)

Welcome to the Evident nondestructive testing (NDT) resource page, a hub for NDT questions, articles, and training materials covering various types of NDT methods, including traditional ultrasonic testing, phased array testing, and eddy current testing. The material found on this page is ideal for both experts and beginners looking to learn more about NDT procedures and devices.

What is NDT?

Nondestructive testing (NDT) is the process of testing or inspecting a material, component, or system without causing damage to the test subject. There are several varieties of nondestructive testing, including traditional ultrasonic flaw detection, phased array testing, and eddy current testing.

Remote visual inspection


How visual inspection works

What’s the main difference between eddy current testing and ultrasonic testing?

Traditional ultrasonic testing (UT) uses the propagation of ultrasonic waves through the test subject to determine if any flaws or defects exist within the subject. Eddy current testing (ECT), on the other hand, uses electromagnetic induction to determine whether there are any internal flaws in conductive materials.


What’s the main difference between phased array testing and eddy current array testing?

Phased array (PA) testing is a variant of ultrasonic testing in which the probe, the device that pulses the sound waves, features an array of elements rather than the single element found in a traditional ultrasonic testing transducer. The phased array technique provides better control over the direction and intensity of the ultrasonic beams. Eddy current array (ECA) testing uses a probe containing an array of eddy current coils to induce the electromagnetic current into conductive materials to detect internal flaws. The quantity and arrangement of coils enables a larger coverage and offers better sensitivity.

pipe inspection


How visual inspection works

What are the benefits of nondestructive testing?

Nondestructive testing provides an abundance of advantages across a range of industries. Since NDT enables the tester to inspect materials such as metals, concrete, ceramics, plastics, and composites—even if only one side of the inspected part is accessible—it can be employed in both quality assurance and in-field testing of materials without needing to damage the test subject. NDT testing can be used to inspect pipes, bridges, dams, and other materials that require routine inspection.


Explore Tutorial Guides

Flaw Detection Resources and Guides

Phased Array Tutorial

This self-guided tutorial is a basic introduction to ultrasonic phased array testing, both for newcomers and for more experienced users who want a review of basic principles.

Ultrasonic Flaw Detection Tutorial

Ultrasonic flaw detection is a powerful NDT technology and a well established test method in many industries, however it can seem complex to a person who has not worked with it.

Eddy Current Array Tutorial

Eddy current array (ECA) is a nondestructive testing technology that provides the ability to electronically drive multiple eddy current coils, which are placed side by side in the same probe assembly.


Additional Nondestructive Testing Training Resources

In addition to our tutorials, explore these NDT resources, including videos, webinars, and application notes to further your knowledge of nondestructive testing.

NDT Videos

Our NDT videos provide deeper insight into NDT technologies as well as their practical uses, such as rail and bridge inspection.

NDT Application Notes

Our NDT application notes offer in-depth looks at NDT testing within specific industries.

NDT Webinars

Discover a range of practical learning materials on NDT testing for both general and industry-specific purposes.

NDT Equipment

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