Investigation of background noise affecting ae data acquisition during tensile loading of frps

Abstract

The method of acoustic emission (AE) allows the detection of damage initiation and growth in composites due to its high sensitivity. However, for the same reason, AE signal acquisition can easily be disrupted by ambient noise. A significant source of noise is the testing machine itself. In this contribution, the qualification of different types of testing machines to perform material testing in combination with AE measurements is investigated. For this purpose, quasi-static tensile tests of ±45° carbon fiber-reinforced epoxy specimens are conducted on a static, an electro-dynamic and a servo-hydraulic machine. Static and electro-dynamic machines in the used setup seem to have no influence on AE data acquisition. Contrary, AE data acquisition on the servo-hydraulic machine proves difficult. Measures, such as increasing the threshold for detection or using a highpass filter to reduce noise have a detrimental effect on data acquisition, since desired signals are discriminated as well.