Oluschinski at 13:26, 12 December 2025

2025-12-12T13:26:31Z

← Older revision		Revision as of 15:26, 12 December 2025
Line 23:		Line 23:
	==Measurement==		==Measurement==

	The sound waves reach the [[Surface\|surface]] of the [[Plastic Component\|component]] or [[Specimen\|test specimen]] and can be detected by piezoelectric sound transducers (see also: [[~~Piezo~~ Ceramic\|piezo ceramic]]). These correspond to the basic design of [[Ultrasonic Standard Sensors\|ultrasonic standard sensors]], but function only as receivers.		The sound waves reach the [[Surface\|surface]] of the [[Plastic Component\|component]] or [[Specimen\|test specimen]] and can be detected by piezoelectric sound transducers (see also: [[Piezoelectric Ceramic\|piezo ceramic]]). These correspond to the basic design of [[Ultrasonic Standard Sensors\|ultrasonic standard sensors]], but function only as receivers.

	The sound transducers are coupled to the surface of the test object. They are tuned to the frequency range of the sound waves to be detected.		The sound transducers are coupled to the surface of the test object. They are tuned to the frequency range of the sound waves to be detected.
Line 29:		Line 29:
	==Evaluation==		==Evaluation==

	The received sound signals represent vibrations of the sound transducer, which are represented by [[HF-Scan\|HF-scans]]. However, to characterize the signal dynamics, the results are usually displayed in sum and rate form. In contrast, by displaying the amplitude values as an HF-scan and applying [[Frequency Analysis\|frequency analysis]] to it, conclusions can be drawn about the damage mechanisms, e.g., in the case of different types of failure in polymer-fibre composites (see also: [[Fibre-reinforced Plastics\|fibre-reinforced plastics]]), and the temporal assignment to individual mechanisms. Further information on the evaluation is explained in the article on [[Sound Emission Testing\|sound emission testing]] (SEP).		The received sound signals represent vibrations of the sound transducer, which are represented by [[HF-Scan\|HF-scans]]. However, to characterize the signal dynamics, the results are usually displayed in sum and rate form. In contrast, by displaying the amplitude values as an HF-scan and applying [[Frequency Analysis\|frequency analysis]] to it, conclusions can be drawn about the damage mechanisms, e.g., in the case of different types of failure in polymer-fibre composites (see also: [[Fibre-reinforced Plastics\|fibre-reinforced plastics model]]), and the temporal assignment to individual mechanisms. Further information on the evaluation is explained in the article on [[Sound Emission Testing\|sound emission testing]] (SEP).

	==See also==		==See also==

Oluschinski: Created page with "{{Language_sel|LANG=ger|ARTIKEL=Akustische Emission}} {{PSM_Infobox}} Acoustic emission FORCETOC ==Definition== Acoustic emissions (sound emissions, SE for short) are elastic stress waves (sound waves) that are generated and propagate as a result of stress reduction in the material volume, specifically due to Micromechanics & Nanomechanics|micromechanical..."

2025-11-28T12:04:53Z

Created page with "{{Language_sel|LANG=ger|ARTIKEL=Akustische Emission}} {{PSM_Infobox}} <span style="font-size:1.2em;font-weight:bold;">Acoustic emission</span> __FORCETOC__ ==Definition== Acoustic emissions (sound emissions, SE for short) are elastic stress waves (sound waves) that are generated and propagate as a result of stress reduction in the material volume, specifically due to Micromechanics & Nanomechanics|micromechanical..."

New page

{{Language_sel|LANG=ger|ARTIKEL=Akustische Emission}}
{{PSM_Infobox}}
<span style="font-size:1.2em;font-weight:bold;">Acoustic emission</span>
__FORCETOC__

==Definition==

Acoustic emissions ([[Sound Emission|sound emissions]], SE for short) are elastic stress waves (sound waves) that are generated and propagate as a result of [[Stress|stress]] reduction in the [[Material & Werkstoff|material]] volume, specifically due to [[Micromechanics & Nanomechanics|micromechanical damage processes]], crack formation (see: [[Fracture Formation|fracture formation]]) and [[Crack Propagation|crack propagation]], and the like. In particular, the boundary areas between the reinforcing material (often fibres) and the matrix (see: [[Fibre–Matrix Adhesion|fibre–matrix adhesion]]) are to be regarded as sound sources in [[Fibre-reinforced Plastics|reinforced plastics]]. With the appropriate measurement technology (see: [[Sound Emission Analysis|sound emission analysis]]), the acoustic emissions can be recorded and linked to ongoing damage mechanisms (see, for example: [[ICIT with AE|Instrumented notch impact test with damage-sensitive sound emission analysis – ICIT with AE]]) and structural variables.

==Generation==

Acoustic emissions are caused by stress concentrations in the [[Material & Werkstoff|material]], which give way in the form of impulses when subjected to corresponding loads, i.e., they are broken down. This causes neighbouring volume elements to vibrate, generating sound waves ('''Fig. 1''').

[[File:Acoustic_Emission-1.jpg]]
{|
|- valign="top"
|width="50px"|'''Fig. 1''':
|width="600px" |Generation of sound waves due to damage to the crack tip when an external load is applied
|}

These are particularly intense when damage processes are involved. Examples include [[Crack Formation|crack formation]] and [[Crack Propagation|crack propagation]] and associated fracture phenomena (see: [[Fracture Types|fracture types]]).

==Measurement==

The sound waves reach the [[Surface|surface]] of the [[Plastic Component|component]] or [[Specimen|test specimen]] and can be detected by piezoelectric sound transducers (see also: [[Piezo Ceramic|piezo ceramic]]). These correspond to the basic design of [[Ultrasonic Standard Sensors|ultrasonic standard sensors]], but function only as receivers.

The sound transducers are coupled to the surface of the test object. They are tuned to the frequency range of the sound waves to be detected.

==Evaluation==

The received sound signals represent vibrations of the sound transducer, which are represented by [[HF-Scan|HF-scans]]. However, to characterize the signal dynamics, the results are usually displayed in sum and rate form. In contrast, by displaying the amplitude values as an HF-scan and applying [[Frequency Analysis|frequency analysis]] to it, conclusions can be drawn about the damage mechanisms, e.g., in the case of different types of failure in polymer-fibre composites (see also: [[Fibre-reinforced Plastics|fibre-reinforced plastics]]), and the temporal assignment to individual mechanisms. Further information on the evaluation is explained in the article on [[Sound Emission Testing|sound emission testing]] (SEP).

==See also==

* [[Acoustic Properties|Acoustic properties]]
* [[Sound Velocity|Sound velocity]]
* [[Non-destructive Testing|Non-destructive testing (NDT)]]

'''References'''

* Bardenheier, R.: Schallemissionsuntersuchungen an polymeren Verbundwerkstoffen. Part I: Das Schallemissionsverfahren als quasi-zerstörungsfreie Werkstoffprüfung. Z. Werkstofftechnik 11 (1980) pp. 41–46
* Bohse, J.: Acoustic Emission Characteristics of Micro-Failure Processes in Polymer Blends and Composites. Compos. Sci. Technol. 60 (2000) 1213–1226 ; https://doi.org/10.1016/S0266-3538(00)00060-9 (access on November 19, 2025)
* Schoßig, M.: Mechanische und bruchmechanische Bewertung von kurzglasfaserverstärkten Polyolefinwerkstoffen unter quasistatischer und dynamischer Beanspruchung. Vieweg+Teubner | Springer Fachmedien Wiesbaden GmbH (2011), (ISBN 978-3-8348-1483-8; see also AMK-Library under B 1-21)

[[Category:Acoustic Test Methods_Ultrasonics]]
[[Category:Velocity]]

Acoustic Emission - Revision history

Oluschinski at 13:26, 12 December 2025