In nondestructive testing, tests are carried out in such a way as to not disturb the specimen’s structural or surface integrity. This type of testing is valuable because the specimen is not destroyed, however, these techniques generally require greater operator skill and the results are not always straightforward to interpret. In general, destructive testing yields much more valuable information on the condition of the specimen.

Types of nondestructive testing

• Acoustic-emission technique
• Acoustic-impact technique
• Eddy-Current inspection
• Ellipsometry
• Interferometry
• Liquid penetrants
• Magnetic-particle inspection
• Radiography
• Thermographic inspection
• Ultrasonic inspection