Fatigue strength improvement of 5083 H11 Al-alloy T-welded joints by shot peening: experimental characterization and predictive approach
2005; Elsevier BV; Volume: 27; Issue: 7 Linguagem: Inglês
10.1016/j.ijfatigue.2005.02.001
ISSN1879-3452
AutoresNaziha Sidhom, Adnen Laamouri, Raouf Fathallah, C. Braham, Henri Paul Lieurade,
Tópico(s)Metal Alloys Wear and Properties
ResumoShot peening improvement of high cycle fatigue (HCF) behavior of metal inert gas (MIG) welded T-joints made from 5083 H11 Al-alloy plates using 5183 Al-alloy welding wires was evaluated by means of four-point bending fatigue tests. The enhancement of the fatigue limits at 2×106 cycles were 135 and 59% for the stress ratios R1=0.1 and R2=0.5, respectively. The properties of near weld toe surfaces, where the micro-crack nucleation occurred, were characterized before and after shot peening. The metallurgical modifications were monitored by micro-hardness measurements, and the in-depth residual stresses have been determined by the hole drilling technique. The surface integrity was examined using a scanning electronic microscope (SEM). Based on multi-axial HCF criterion of Sines and taking into account the different surface properties, a local predictive approach was developed. It allows correlating quantitatively the influence of MIG-welding and shot peening on the HCF performance of the Al-alloy 5083 H11. The characteristic parameters of the proposed approach have been calibrated, in order to obtain secure predictions, for the two cases of welded and peened welded T-joints.
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