ABSTRACT
In Acoustic Emission Testing, the specimen is stressed by applying a load. External or internal forces are used to make discontinuities emit stress waves. Acoustic energy is carried at all frequencies from well below to well above the audible range. By listening at frequencies between the audible and ultrasonic ranges, discontinuity growth and structural integrity can be examined. Acoustic Emission Testing can also be used with materials such as fiberglass and other composite materials. Acoustic emission test loads are applied in various ways that can include:
• Hydrostatic, hydraulic or pneumatic loading. Typically pressure vessels are tested by applying pressure internal to the vessel. Storage tanks, which are not classed as pressure vessels, are tested.
