Initiation and short crack growth behaviour of environmentally induced cracks in AA5083 H131 investigated across time and length scales

DOI: 10.1515/corrrev-2019-0044

Authors: Visweswara C. Gudla (The University of Manchester) , Alistair Garner (The University of Manchester) , Malte Storm (Diamond Light Source) , Parmesh Gajjar (The University of Manchester) , James Carr (The University of Manchester) , Benjamin C. Palmer (Case Western Reserve University) , John J. Lewandowski (Case Western Reserve University) , Philip J. Withers (The University of Manchester) , N. J. Henry Holroyd (Case Western Reserve University; The University of Manchester) , Timothy L. Burnett (The University of Manchester)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Corrosion Reviews , VOL 0

State: Published (Approved)
Published: June 2019
Diamond Proposal Number(s): 18165

Abstract: Environmentally induced cracking (EIC) in a sensitized high-strength AA5083 H131 alloy has been investigated using time-lapse synchrotron X-ray computed tomography combined with post-mortem correlative characterization. Small corrosion features deliberately introduced in a pre-exposure step were found to be the site of initiation for over 95% of the 44 EIC cracks that developed under slow strain rate testing. Detailed analysis using three-dimensional electron backscatter diffraction and energy-dispersive spectroscopy analysis of a single crack confirmed the intergranular nature of the cracks from the start and that the pre-exposure corrosion was associated with an α-AlFeMnSi particle cluster. It also appears that several cracks may have initiated at this site, which later coalesced to form the 300-μm-long crack that ultimately developed. Of further note is the fact that initiation of the EIC cracks across the sample started below the yield strength and continued beyond the ultimate tensile strength. The most rapid crack propagation occurred during sample extension following a period of fixed displacement.

Journal Keywords: 4D; correlative tomography; EIC; humid air; hydrogen embrittlement; non-propagating cracks

Diamond Keywords: Alloys

Subject Areas: Materials, Engineering


Instruments: I13-2-Diamond Manchester Imaging

Added On: 08/08/2019 09:40

Documents:
10.1515_corrrev-2019-0044.pdf

Discipline Tags:

Materials Engineering & Processes Materials Science Engineering & Technology Metallurgy

Technical Tags:

Imaging Tomography