Alkaline corrosion properties of laser-clad aluminum/titanium coatings. Issue 1 (5th January 2015)

• Record Type: Journal Article
• Authors: Aggerbeck, Martin; Herbreteau, Alexis; Rombouts, Marleen; Verwimp, Jo; Ambat, Rajan
• Is Part Of: Anti-corrosion methods and materials. Volume 62:Issue 1(2015)
• Page Start: 37
• Page End: 47
• Publication Date: 2015-01-05
• Subjects: Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1108/ACMM-07-2013-1290
• Languages: English
• ISSNs: 0003-5599

Abstract

<abstract> <title> <x content-type="archive" xml:space="preserve">Abstract</x> </title> <sec> <title content-type="abstract-heading">Purpose</title> <p> – The purpose of this paper is to study the use of titanium as a protecting element for aluminum in alkaline conditions. </p> </sec> <sec> <title content-type="abstract-heading">Design/methodology/approach</title> <p> – Aluminum coatings containing up to 20 weight per cent Ti6Al4V were produced using laser cladding and were investigated using light optical microscope, scanning electron microscope – energy-dispersive X-ray spectroscopy and X-Ray Diffraction, together with alkaline exposure tests and potentiodynamic measurements at pH 13.5. </p> </sec> <sec> <title content-type="abstract-heading">Findings</title> <p> – Cladding resulted in a heterogeneous solidification microstructure containing an aluminum matrix with supersaturated titanium (<1 weight per cent), Al<sub>3</sub>Ti intermetallics and large partially undissolved Ti6Al4V particles. Heat treatment lowered the titanium concentration in the aluminum matrix, changed the shape of the Al<sub>3</sub>Ti precipitates and increased the degree of dissolution of the Ti6Al4V particles. Corrosion testing showed significant localized dissolution of the aluminum matrix. </p> </sec> <sec> <title content-type="abstract-heading">Research limitations/implications</title> <p> – Increased titanium concentration and heat treatment gave improved alkaline corrosion properties. At pH 13.5, the Al<sub>3</sub>Ti phases were protected, while the aluminum matrix corroded. </p> </sec> <sec> <title content-type="abstract-heading">Practical implications</title> <p> – For alkaline corrosion-protection of aluminum in the automobile industry, titanium might be useful at pH values below 13.5 or by using other coating techniques. </p> </sec> <sec> <title content-type="abstract-heading">Originality/value</title> <p> – This is the first study testing the use of titanium as a protective element of aluminum in stringent alkaline conditions.</p> </sec> </abstract>