Loughborough University
Leicestershire, UK
LE11 3TU
+44 (0)1509 263171
Loughborough University

Loughborough University Institutional Repository

Please use this identifier to cite or link to this item: https://dspace.lboro.ac.uk/2134/4412

Title: Novel methods, incorporating pre- and post-anodising steps, for the replacement of the Bengough–Stuart chromic acid anodising process in structural bonding applications
Authors: Yendall, Keith A.
Critchlow, Gary W.
Keywords: Aluminium alloy
Sulphuric acid anodising
Electro-deoxidiser
Phosphoric acid dip
Issue Date: 2009
Publisher: © Elsevier
Citation: Yendall, K.A. and CRITCHLOW, G.W., 2009. Novel methods, incorporating pre- and post-anodising steps, for the replacement of the Bengough–Stuart chromic acid anodising process in structural bonding applications. International Journal of Adhesion and Adhesives, 29 (5), pp. 503-508
Abstract: The present investigation focuses on novel anodising processes which are being developed for the replacement of the hexavalent chromium containing 40/50V Bengough-Stuart process, with particular emphasis on their resultant performance in structurally bonded systems used in the demanding and harsh environments encountered on operational aircraft. An electrolytic phosphoric acid based deoxidiser (EPAD)has been studied in combination with a standard sulphuric acid anodise. It has been shown that the EPAD provides an open porous structure in order to enhance adhesion to the modified sulphuric acid anodised (SAA) surface. Additionally, a post anodising (PAD) treatment has been used to aid structural adhesion in combination with the SAA processes. 2 As a control, the standard 40/50V Bengough-Stuart chromic acid anodising (CAA) has been used as a baseline performance indicator in adhesion tests. Single lap shear (SLS) and modified Boeing wedge tests were used to determine adhesion performance. SLS tests were used to determine initial, dry joint strengths whilst wedge test joints immersed in deionised water for up to 100 hours gave a measure of joint durability. Overall, excellent initial joint strengths and durability have been found with both EPAD plus SAA and PAD plus SAA processes suggesting that these environmentally benign treatments may be used as possible drop-in replacements for the currently used hexavalent chromium process. Electron microscopy has been used to investigate the topographical changes introduced to the surface by the various surface pretreatments under investigation to provide an explanation for the observed adhesion test results.
Description: This article was published in the journal, International Journal of Adhesion and Adhesives [© Elsevier]. The definitive version is available at: http://www.sciencedirect.com/science/journal/01437496
Version: Accepted for publication
DOI: doi:10.1016/j.ijadhadh.2008.11.001
URI: https://dspace.lboro.ac.uk/2134/4412
ISSN: 0143-7496
Appears in Collections:Published Articles (Materials)

Files associated with this item:

File Description SizeFormat
kaypaper.pdf601.35 kBAdobe PDFView/Open

 

SFX Query

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.