Non Destructive Testing is a method used to detect discontinuities that cannot be detected on the surface or internal structure of the material without damaging the material. The most widely used non-destructive testing methods in the industry are visual test, magnetic particle test, penetrant test, ultrasonic test, radiographic test, acoustic emulsion test and eddy current test. Non-destructive testing methods apply, material properties, part geometry, part thickness, etc. is limited according to.

The date when the Non-Destructive Testing was started is not known exactly. But people have been doing non-destructive tests since ancient times. Centuries before the definition of “NDT”, people tried to determine the size, shape and even superficial imperfections of objects by looking at them. Visual Inspection was officially accepted as the NDT method in 1988.