In situ 3D characterization of high temperature fatigue damage mechanisms in a cast aluminum alloy using synchrotron X-ray tomography

Sébastien Dezecot (1, 2, 3) , Jean-Yves Buffiere (1) , Alain Köster (2) , Vincent Maurel (2) , Fabien Szmytka (3) , Eric Charkaluk (4, 5, 6) , Nora Dahdah (5, 7) , Ahmed El Bartali (5, 7) , Nathalie Limodin (5, 4) , Jean-Francois Witz (5, 4)

1 MATEIS - Matériaux, ingénierie et science [Villeurbanne]
2 CDM - Centre des Matériaux
3 PSA - PSA Peugeot - Citroën
4 CNRS - Centre National de la Recherche Scientifique
5 LML - Laboratoire de Mécanique de Lille - FRE 3723
6 LMS - Laboratoire de mécanique des solides
7 Centrale Lille

Fatigue tests were performed at 250 °C on a cast AlSi7Cu3Mg aluminum alloy and monitored with Synchrotron in situ X-ray tomography in order to understand the micro-mechanisms of crack initiation and propagation. The analysis of the 3D images reveals that internal shrinkage pores are responsible for the main crack initiation. Crack propagation is mainly due to the complex and highly interconnected network of hard particles of the eutectic regions.

Keywords: High-temperature; Fatigue; Tomography; Cracks; Aluminum alloy

Domains: Engineering Sciences [physics]

Sébastien Dezecot, Jean-Yves Buffiere, Alain Köster, Vincent Maurel, Fabien Szmytka, et al.. In situ 3D characterization of high temperature fatigue damage mechanisms in a cast aluminum alloy using synchrotron X-ray tomography. Scripta Materialia, 2016, 113, pp.254-258. ⟨10.1016/j.scriptamat.2015.11.017⟩. ⟨hal-01255815⟩