caa a22 4500 463229045 CHVBK 20180405153236.0 cr unu---uuuuu 170326e20070701xx s 000 0 eng 10.1007/s10853-006-0993-8 doi (NATIONALLICENCE)springer-10.1007/s10853-006-0993-8 On the non-destructive detection of fatigue damage in industrial aluminium alloys by positron annihilation [Elektronische Daten] [Uwe Holzwarth, Petra Schaaff] The average positron lifetime has been determined non-destructively and in-situ during fully symmetric push-pull fatigue experiments in the bulk material of the aluminium alloys 2024 T3 and 7075 T6 using a servo-hydraulic fatigue testing system equipped with a mobile positron beam produced by a 72Se/72As generator (initial activity of ≈ 0.9MBq; average positron penetration depth ≥1mm). Contrary to earlier investigations on stainless steel using the same experimental approach, no variation of the average positron lifetime could be observed during fatigue and neither early nor late stages of fatigue damage could be revealed. It is concluded that fatigue induced changes of the defect spectra in technologically relevant aluminium alloys are masked for the present method by saturation trapping in precipitates. A sufficiently high increase of the dislocation density and the creation of vacancy clusters must be confined to the vicinity of propagating fatigue cracks or the fatal fatigue crack. Therefore the zone with sufficient detectable fatigue damage has not enough statistical weight to modify the average positron lifetime of the aluminium alloy bulk material. Springer Science+Business Media, LLC, 2007 Holzwarth Uwe Institute for Health and Consumer Protection, European Commission, Joint Research Centre, Via E. Fermi 1 (T.P. 500), 21020, Ispra, VA, Italy aut Schaaff Petra Institute for Health and Consumer Protection, European Commission, Joint Research Centre, Via E. Fermi 1 (T.P. 500), 21020, Ispra, VA, Italy aut Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/14(2007-07-01), 5620-5628 0022-2461 42:14<5620 2007 42 10853 https://doi.org/10.1007/s10853-006-0993-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10853-006-0993-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Holzwarth Uwe Institute for Health and Consumer Protection, European Commission, Joint Research Centre, Via E. Fermi 1 (T.P. 500), 21020, Ispra, VA, Italy aut NATIONALLICENCE 700 1- Schaaff Petra Institute for Health and Consumer Protection, European Commission, Joint Research Centre, Via E. Fermi 1 (T.P. 500), 21020, Ispra, VA, Italy aut NATIONALLICENCE 773 0- Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/14(2007-07-01), 5620-5628 0022-2461 42:14<5620 2007 42 10853 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer