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Nondestructive testing is not confined to crack

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Nondestructive testing is not confined to crack detection. Other discontinuities include porosity, wall thinning from corrosion and many sorts of disbonds. Nondestructive material characterization is a growing field concerned with material properties including material identification and microstructural characteristics — such as resin curing, case hardening and stress — that have a direct influence on the service life of the test object. Methods and Techniques Nondestructive testing has also been defined by listing or classifying the various techniques. 1-3 This sense of nondestructive testing is practical in that it typically highlights methods in use by industry. In the Nondestructive Testing Handbook, the word method is used for a group of test techniques that share a form of probing energy. Ultrasonic test methods, for example, use acoustic waves faster than sound. Infrared and thermal testing and radiographic testing both use electromagnetic radiation, each in a defined wavelength range. A technique, in contrast, has features that adapt the method to the application. Through-transmission immersion testing is a technique of the ultrasonic method, for example. Purposes of Nondestructive Testing Since the 1920s, the art of testing without destroying the test object has developed 2 Electromagnetic Testing P ART 1. Nondestructive Testing M OVIE . Need for nondestructive testing.
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from a laboratory curiosity to an indispensable tool of fabrication, construction, manufacturing and maintenance processes. No longer is visual testing of materials, parts and complete products the principal means of determining adequate quality. Nondestructive tests in great variety are in worldwide use to detect variations in structure, minute changes in surface finish, the presence of cracks or other physical discontinuities, to measure the thickness of materials and coatings and to determine other characteristics of industrial products. Scientists and engineers of many countries have contributed greatly to nondestructive test development and applications. The various nondestructive testing methods are covered in detail in the literature but it is always wise to consider objectives before details. How is nondestructive testing useful? Why do thousands of industrial concerns buy the testing equipment, pay the subsequent operating costs of the testing and even reshape manufacturing processes to fit the needs and findings of nondestructive testing? Modern nondestructive tests are used by manufacturers (1) to ensure product integrity and in turn reliability, (2) to avoid failures, prevent accidents and save human life (see Figs. 1 and 2), (3) to make a profit for the user, (4) to ensure customer satisfaction and maintain the manufacturer’s reputation, (5) to aid in better product design, (6) to control manufacturing processes, (7) to lower manufacturing costs, (8) to maintain uniform quality level and (9) to ensure operational readiness.
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  • Fall '19
  • The Land, Nondestructive testing, electromagnetic testing

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