How it Works?
Acoustic Emission (AE) refers to the generation of transient elastic waves produced by a sudden redistribution of stress in a material. When a structure is subjected to an external stimulus (change in pressure, load, or temperature), localized sources trigger the release of energy, in the form of stress waves, which propagate to the surface and are recorded by sensors. With the right equipment and setup, motions on the order of picometers (10 -12 m) can be identified. In composites, matrix cracking and fibre breakage and debonding contribute to acoustic emissions.
- First, the signal has its origin in the material itself, not in an external source.
- Second, acoustic emission detects movement, while most other methods detect existing geometrical discontinuities.
How Atomic Technologies uses AE?
- The whole volume of the structure to be inspected non-intrusive in a single loading operation.
- It is not necessary to scan the structure looking for local defects; it is only necessary to connect a suitable number of fixed sensors; which are typically placed 1 to 6 m (4 to 20 ft) apart.
- This leads to major savings in testing large structures, for which other methods require removal of insulation, decontamination for entry to vessel interiors, or scanning of very large areas.
- AE inspection is used to identify areas with structural problems, and other NDT methods are then used to identify more precisely the nature of the emitting defects. Our inspection program combines both AE and other NDT techniques to arrive at the best accurate diagnosis.