Pretreatments of Al-2024 T3 alloy for BTSE silane deposition
department or school: Science, Faculty of
department or school: Chemistry, Department of
data provider: DSpace
degree campus: UBCV
creator: Lee, Michael Che-Chiang
issued: 2009-10-28T23:07:59Z
issued: 2002
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Work in this thesis studied different alkaline etching procedures performed on Al-2024 alloy prior to deposition of bis-triethoxysilylethane (BTSE). X-ray photoelectron spectroscopy and scanning electron microscopy were used to study the chemistry and morphology of the surfaces formed after the various pretreatments and coatings have been applied. The corrosion performance of these samples were assessed using polarisation curve measurements and immersion testing. Sonicating tests were performed to determine, semi-quantitatively, the adhesion of BTSE to Al-2024 panels after application of the various pretreatments. Alkaline etching of the coated and uncoated Al-2024 panels was performed using 10% NaOH in deionised water, varying the duration of the treatment from 1 minute to 10 minutes. It is shown on uncoated Al-2024 that longer etching times increase surface roughness of the substrate, but also reduce corrosion resistance, cause copper enrichment at the surface, and form loosely-bonded etching products which affect the subsequent silane deposition steps. BTSE solutions varying from 1% to 10% (v/v) BTSE were used to coat the pretreated panels. It is found that BTSE-coated samples perform better than their uncoated counterparts in corrosion testing, and that more-concentrated BTSE solutions on identically prepared panels produce thicker coatings, with better passivation. It is also found that, while increasing the alkaline etching time may lead to conditions where more BTSE is deposited to the surface, this "enhanced" silane layer is not as securely-bonded to the surface and will not aid in the passivation of the substrate. Finally, the effects of the HNO₃ desmutting step were studied by varying the treatment times that the Al-2024 panels received in 10% FINO₃ after 1 minute of alkaline etching. It is found that for up to 30 minutes of treatment, FINO₃ is beneficial to silane deposition as it removes the etching product created during the NaOH treatment, builds up th…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/14287
extent: 4627268 bytes
format: application/pdf
note: Pretreatments of Al-2024 T3 Alloy for BTSE Silane Deposition by Michael Che-Chiang Lee B.Sc. (Hons), The University of Western Ontario, 1999 A THESIS SUBMITTED IN PARTIAL F U L F I L L M E N T OF THE REQUIREMENTS FOR THE D E G R E E OF M A S T E R OF SCIENCE in THE F A C U L T Y OF G R A D U A T E STUDIES Department of Chemistry We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH C O L U M B I A August 2002 © Michael Che-Chiang Lee, 2002 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my writ ten permission. Department of ( g ^ / T / V / E 77? ^ The University of British Columbia Vancouver, Canada DE-6 (2/88) Abstract Work in this thesis studied different alkaline etching procedures performed on Al-2024 alloy prior to deposition of bis-triethoxysilylethane (BTSE). X-ray photoelectron spectroscopy and scanning electron microscopy were used to study the chemistry and morphology of the surfaces formed after the various pretreatments and coatings have been applied. The corrosion performance of these samples were assessed using polarisation curve measurements and immersion testing. Sonicating tests were performed to determine, semi-quantitatively, the adhesion of BTSE to Al-2024 panels after application of the various pretreatments. Alkaline etching of the coated and uncoated Al-2024 panels was performed using 10% NaOH in deionised water, varying the duration of the treatment from 1 minute to 10 minutes. It is shown on uncoated Al-2024 that longer etching times increase surface roughness of the substrate…
has type: Thesis/Dissertation
date issued: 2003-11
is shown at: 10.14288/1.0061289
language: eng
degree discipline: Chemistry
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/14287