Nondestructive testing or Non-destructive testing (NDT) is a wide group of analysis techniques used in science and industry to evaluate the properties of a material, component surface & subsurface without causing damage or effect to their future performance or properties. Non-destructive testing is used to detect abnormalities in physical, chemical or electrical characteristics.
NDT provides an edge over conventional methods as it is a fast, cheap and easy process. In 1930s, non destructive testing, where it had been heard of at all, was generally considered an evil. Later it became a necessary evil. For a number of years now NDT has been a necessary aid. NDT has saved uncounted thousands of lives. Non destructive testing is not confined to crack detection. Other discontinuities include porosity, wall thinning from corrosion and many sorts of disbond.
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