FREQUENCY SPECTRA OF ACOUSTIC EMISSION

Theoretical Elements of Acoustic Emission Spectra

Study of the Frictional Surface Damage Using Acoustic Emission Method

In this study, the change at rubbing surfaces has been investigated experimentally using an acoustic emission signal monitoring system. A steel ring is slipped on the surface of  a metallic sheet to simulate frictional conditions. The mechanical disturbances caused by the movement of the ring produce stress waves propagating along the sheet surface. The out of plane displacement of the sheet su...

Flexural monitoring of carbon fiber/epoxy composite by acoustic emission

Carbon / epoxy composite is one of the most useful polymer matrix composites that has special properties such as high strength-to-weight ratio, high hardness, high corrosion resistance, Resistance to nuclear radiation has high consumption in different industries such as aerospace industry. Therefor monitoring of loading of this type of composite is important. In order to determine failure mecha...

Pulsar spectra of radio emission

We have collected pulsar flux density observations and compiled spectra of 281 objects. The database of Lorimer et al. (1995) has been extended to frequencies higher than 1.4 GHz and lower than 300 MHz. Our results show that above 100 MHz the spectra of the majority of pulsars can be described by a simple power law with average value of spectral index < α >= −1.8 ± 0.2. A rigorous analysis of s...

Evaluation of Acoustic Emission Inspection of Oil Tank Floor via Tank Bottom Plates Thickness Measurement

This paper deals with an inspection of defects including corrosion and leakage by Acoustic Emission (AE) in an oil tank floor. In contrast to intrusive methods such as magnetic flux leakage, eddy current or ultrasonic, there is no need to emptying and entering the tank in AE method in order to inspection. In this research AE investigation and AE source location is presented in detail. The resul...