What are the seven methods of non-destructive evaluation (NDE)?

What are the seven methods of non-destructive evaluation (NDE)?

• A. Visual, Magnetic particle
• B. Liquid penetrant, Ultrasonic
• C. Radiographic, Acoustical emission
• D. None of the above

Answer: (D)

Non-destructive evaluation (NDE) encompasses a variety of testing techniques used to evaluate the properties of a material, component, or system without causing damage. The primary methods included in NDE cover a wide range of applications and can be categorized as follows:

1. Visual Inspection: The most basic form of NDE, where the surface of the material is examined with the naked eye or aided by tools such as magnifying glasses or cameras to detect surface defects.

2. Magnetic Particle Testing: This method is used for detecting surface and near-surface discontinuities in ferromagnetic materials through the application of magnetic fields and the use of magnetic particles.

3. Liquid Penetrant Testing: A technique that reveals surface-breaking defects by applying a liquid penetrant to the surface, allowing it to seep into any cracks, followed by a developer that draws the penetrant back out to create a visible indication.

4. Ultrasonic Testing: Involves sending high-frequency sound waves into a material. Reflections from internal flaws are analyzed to determine the presence and size of defects.

5. Radiographic Testing: This technique uses X-rays or gamma rays to create images of the internal structure of a component,