Engineering: UKRI EPSRC CDT EngD Scholarship: The Influence of Oxygen Reduction on Corrosion Protective Organic Coating Failure

Sponsor Company: BASF Coatings GmbH

Project Supervisors:

Academic Supervisors- Primary: Professor Geraint Williams, Secondary: Professor James Sullivan

Industry Supervisor- Dr Patrick Keil

Aligned programme of study: EngD in Materials, Modelling and Manufacturing

Mode of study: Full-time

Expected Interview Date: March-April 2023

Background:

It is well known that localized corrosion causes paint films to delaminate from metal surfaces, through a mechanism involving anodic metal dissolution at a penetrative coating defect, coupled to cathodic oxygen reduction occurring on the adjacent organic-coated metal. This cathode-driven disbondment of the organic coating is thought to proceed through the formation of an under-film alkaline environment, which promotes loss of adhesion through hydrolysis of interfacial bonds, polymer degradation, and dissolution of amphoteric oxide layers. However, it is also thought that the presence of highly reactive intermediate species in the oxygen reduction reaction, such as peroxides and free radicals may also play an important role in de-adhesion on certain metal surfaces.

This project forms part of a larger partnership involving BASF Coatings Ltd, in collaboration with Swansea University and Imperial College London, where the main theme will involve furthering knowledge of corrosion-induced failure of protective organic coatings when applied to metal surfaces. The principal focus of this project will be directed towards a fundamental understanding of the role of oxygen reduction in organic coating degradation via a cathodic delamination mechanism.

This project aims to fundamentally understand the role of the oxygen reduction reaction on the corrosion-driven failure of protective organic coatings applied to steel and galvanized steel surfaces. The principal objectives will comprise the following:

• A correlation of oxygen reduction rate, determined electrochemically on bare metal surfaces with organic coating failure rate under atmospheric conditions when the same surfaces are coated with a protective organic layer.
• An understanding of the influence of surface oxide composition and the presence of thin film pretreatments on oxygen reduction rate and the associated tendency to undergo organic coating disbondment.
• A mechanistic understanding of the interfacial processes associated with oxygen reduction which cause de-adhesion at the metal-polymer interface, along with a knowledge of any chemical changes produced within the polymer film.

Project Aims:

The research will concentrate on three specific areas of interest:

(i) Developing methodologies which enable the oxygen reduction reaction to be characterized in situations where metal surfaces such as cold-rolled steel and galvanized steel are coated with an organic layer.

(ii) Gaining mechanistic information of the cathodic disbondment process by identifying chemical and physical changes in the de-adhered polymer film caused by interfacial oxygen reduction

(iii) A comparison of electrochemical measurements of oxygen reduction rates on various metal substrates with empirically gathered organic coating cathodic delamination rates to identify controlling factors such as surface composition/chemistry; understand the means to mitigate against cathode-driven coating failure.

The investigation will be carried out using comprehensive in-situ and ex-situ electrochemical characterization by means of scanning Kelvin Probe (SKP), Scanning Vibrating electrode technique (SVET), alongside potentiodynamic and electrochemical impedance spectroscopy methods in the laboratories of the Swansea University corrosion research group. Surface chemical and structural characterization will be carried using a world class suite of instrumentation including X-ray-photoelectron spectroscopy (XPS), glancing angle X-ray diffraction (XRD), and field emission gun scanning electron microscopy (FEG-SEM), available in the Materials Research Centre at the Faculty of Science & Engineering.

COATED M2A:

COATED M2A recognises applicants have a variety of backgrounds with different educational and research experiences. We do not expect applicants to be proficient users of any techniques/equipment mentioned, at the time of application. Our focus is to upskill our participants and training will be provided.

COATED M2A in the Faculty of Science and Engineering is a Swansea University initiative which provides postgraduate research training in partnership with industry, providing access to world class laboratories and a wealth of academic and industry expertise. COATED M2A is committed to providing top quality research opportunities within an inclusive environment, funded by the Engineering and Physical Sciences Research Council (EPSRC), Swansea University and Industry partners.

Interwoven through the research study are business, technical and entrepreneurial courses, designed to support and prepare participants for a senior role in industry or academia, on completion of their studies.

The Athena SWAN charter recognises work undertaken by institutions to advance gender equality. The College of Engineering is an Athena SWAN silver award holder and is committed to addressing unequal gender representation. Applications from women and other under-represented groups are particularly welcomed. 

All applications will be anonymised prior to short listing.

Eligibility

Candidates must normally hold at minimum (or expect to obtain by the start date) an undergraduate degree at 2.1 level (or Non-UK equivalent as defined by Swansea University), or a combination of degree and equivalent experience to the same level. 

English Language requirements: If applicable – IELTS 6.5 overall (with at least 6.0 in each individual component) or Swansea recognised equivalent.

Studentships for October 2023 entry are open to candidates of any nationality; however, please note:

International students (including EU countries) can apply, but due to UKRI funding rules, no more than 30% of the Centre for Doctoral Training (CDT) in Functional Industrial Coatings projects can be allocated to international students. Once the cap is reached, studentships will only be open to applicants eligible for tuition fees at the UK rate, as defined by UKCISA regulations.

Further details about eligibility, including information about the ‘international cap’ can be found at: Eligibility (identifying if you are a home or international student) – UKRI.

ATAS

Please note that the programme requires some applicants to hold ATAS clearance; further details on ATAS scheme eligibility are available on the UK Government website.

ATAS clearance IS NOT required  to be held as part of the scholarship application process, successful award winners (as appropriate) are provided with details as to how to apply for ATAS clearance in tandem with scholarship course offer.