Assessment of the fatigue crack closure phenomenon in damage-tolerant aluminium alloy by in-situ high-resolution synchrotron X-ray microtomography


Toda, H., Sinclair, I., Buffière, J.-Y., Maire, E., Connolley, T., Joyce, M., Khor, K.H. and Gregson, P. (2003) Assessment of the fatigue crack closure phenomenon in damage-tolerant aluminium alloy by in-situ high-resolution synchrotron X-ray microtomography. Philosophical Magazine, 83, (21), 2429-2448. (doi:10.1080/1478643031000115754).

Download

Full text not available from this repository.

Description/Abstract

Synchrotron X-ray microtomography has been utilized for the in-situ observation of steady-state plane-strain fatigue crack growth. A high-resolution experimental configuration and phase contrast imaging technique have enabled the reconstruction of crack images with an isotropic voxel with a 0.7 µm edge. The details of a crack are readily observed, together with evidence of the incidence and mechanical influence of closure. After preliminary investigations of the achievable accuracy and reproducibility, a variety of measurement methods are used to quantify crack-opening displacement (COD) and closure from the tomography data. Utilization of the physical displacements of microstructural features is proposed to obtain detailed COD data, and its feasibility is confirmed. Loss of fracture surface contact occurs gradually up to the maximum load. This is significantly different from tendencies reported where a single definable opening level is essentially assumed to exist. The closure behaviour is found to be attributable mainly to pronounced generation of mode III displacement which may be caused by local crack topology. Many small points of closure still remain near the crack tip, suggesting that the near-tip contact induces crack growth resistance. The effects of overloading are also discussed.

Item Type: Article
ISSNs: 1478-6435 (print)
Related URLs:
Subjects: T Technology > TN Mining engineering. Metallurgy
Q Science > QC Physics
Divisions: University Structure - Pre August 2011 > School of Engineering Sciences
ePrint ID: 22491
Date Deposited: 24 Mar 2006
Last Modified: 27 Mar 2014 18:11
Contact Email Address: I.Sinclair@soton.ac.uk
URI: http://eprints.soton.ac.uk/id/eprint/22491

Actions (login required)

View Item View Item