Non-Destructive Testing of Materials

In this paper an attempt is made to describe the technique, applications and the advantages or otherwise of the various Non-destructive methods of the examination of materials.

In the not too distant past the only methods used for the examination of materials were based on the assessment of their physical properties, most of these methods resulted in the ultimate destruction of the specimen examined. Thus the speciment examined was no use for service itself, but by its destruction it led the examiner to conclude that parts made from the material similar to that of the specimen examined would possess physical properties revealed by the examination, and if, those properties were up to specification, the parts like the one examined could be accepted. This was alright as far as the representative piece was concerned but the argument against it was that the part that actually goes into service has not been tested, and may be that during the process of manufacture the part develops certain defects which though, invisible to the naked eye may be serious enough to cause a failure in actual service.