What is Non-Destructive Testing (NDT)?

Nondestructive testing is a testing and analysis technique used in industry to evaluate the performance of materials, components, structures or systems to detect differences in properties or weld defects and discontinuities without causing damage to the original part. Non-destructive testing is also known as non-destructive testing (NDE), non-destructive inspection (NDI) and non-destructive evaluation (NDE).

Non-destructive testing methods rely on the use of electromagnetic radiation, sound and other signal transformations to examine the integrity, composition or condition of various items (metals and non-metals, food, cultural relics and antiquities, infrastructure) without altering the item being inspected. Visual inspection (VT) is a commonly used nondestructive testing method, often enhanced by direct or remote observation using magnification, borescopes, cameras, or other optical devices. The internal structure of the sample can be volumetrically examined with penetrating radiation (RT), such as X-rays, neutrons or gamma radiation. Ultrasonic Testing (UT) is Ultrasonic Testing (UT), another volumetric non-destructive testing method - a mechanical signal (sound) is conditioned in the item under test and the amplitude and distance from the search unit (transducer) is evaluated. Another common NDT method used for ferrous materials involves the application of fine iron particles (suspended in liquid or dry powder - fluorescent or colored) which are applied continuously or residually to the part when magnetized. Particles will be attracted to the leakage magnetic field on or in the test object and form indications on the surface of the object (particle collection), which are assessed visually. The contrast and probability of detection of naked eye visual inspection can often be enhanced by using liquids to penetrate the surface of the test item to visualize defects or other surface conditions. This method (liquid penetrant testing) (PT) involves the use of a dye, fluorescent or colored (usually red), suspended in a fluid, for non-magnetic materials, usually metals.

Analysis and recording of non-destructive failure modes can also be done using high-speed camera continuous recording (animation loop) until a failure is detected. Detecting faults can be done using an acoustic Detector or manometer that produces a signal that triggers a high-speed camera. These high-speed cameras have an excellent recording mode that captures some non-destructive failures. After the failure, the high-speed camera will stop recording. Captured images can be played back in slow motion, showing exactly what happened before, during and after the lossless event, image by image.