DocumentCode :
2284960
Title :
Acoustic emission diagnostics of faulty fusion in welding
Author :
Apasov, A.M. ; Apasov, A.A.
Author_Institution :
Department of ferrous metals metallurgy, Yurga Institute of Technology, Tomsk Polytechnic University, Russia
fYear :
2012
fDate :
18-21 Sept. 2012
Firstpage :
1
Lastpage :
5
Abstract :
A brief analysis of faulty fusion in welding is presented. A physical model revealing the mechanism of generation of elastic mechanical waves which occur at the moment of metal structure formation in faulty fusion is suggested. As a result the phenomenon of inception of acoustic emission was determined for the first time ever, the information-bearing parameters characterizing real-time initiation of faulty fusion amid existing disturbances were determined. It was found out that in pulse argon arc welding of austenitic steel with intense cooling of heat-affected zone, short compressing and pulling stresses in metal during its crystallization take place. This stresses are added to the stresses taking place in a faulty fusion mouth and lead to rupture of interatomic bonds and emission of elastic mechanical waves interpreted as acoustic emission where acoustic emission signals are distributed by an amplitude attribute. Besides it was determined that acoustic emission signals originated by the processes of faulty fusion initiation and development and the process of crack formation registered in the same amplitude analyzer channel are distributed by the number of acoustic emission impulses.
Keywords :
acoustic emission; acoustic signal processing; arc welding; austenitic steel; compressive strength; cooling; cracks; crystallisation; elastic waves; fault diagnosis; fracture; mechanical engineering computing; stress analysis; acoustic emission diagnostics; acoustic emission impulses; acoustic emission signals; amplitude analyzer channel; amplitude attribute; austenitic steel; crack formation; crystallization; elastic mechanical wave emission; elastic mechanical wave generation; faulty fusion initiation; faulty fusion mouth; heat-affected zone; information bearing parameter; intense cooling; interatomic bonds; metal structure formation; pulling stresses; pulse argon arc welding; real-time initiation; rupture; short compressing; Acoustic emission; Atomic measurements; Heating; Metals; Oscillators; Stress; Welding; acoustic emission; austenitic steel; elastic mechanical waves; faulty fusion in welding; physical model; signal; the process of crack formation;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Strategic Technology (IFOST), 2012 7th International Forum on
Conference_Location :
Tomsk
Print_ISBN :
978-1-4673-1772-6
Type :
conf
DOI :
10.1109/IFOST.2012.6357718
Filename :
6357718
Link To Document :
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