Reliability Analysis of Adhesively Bonded Fibre Reinforced Polymer Composites

The Brunel Composites Centre (BCC) conducts research in phenomena that take place at the interface of composites with other types of materials. Current research projects cover composites processing, composites joints, and composites performance assessment through modelling and testing.

The objective of this PhD research study is to develop a framework that can assess the reliability of adhesively bonded joints in terms of mechanical performance.

The increasing use of fibre reinforced polymer (FRP) composite materials in a wide range of applications increases the use of similar and dissimilar joints. Due to the architecture of FRPs, the use of traditional mechanical fastening joining methods is damaging, restrictive and cost-intensive. In contrast, adhesive bonding technology is one of the most widely used joining methods for composites because it allows flexibility in selecting materials, improved production efficiency, and cost reduction. Yet, because of the complex nature of their failure and the fact that not all defects can be fully verified by inspection and testing, these joints are conservatively designed, limiting the potential of composite materials in weight reduction, cost-saving, and performance.

While many studies have investigated the effect of defects on the failure of adhesive bonds and others aimed at developing non-destructive testing technologies to inspect these joints, there is a need to identify the statistical uncertainties of these defects and understand their correlation and effect when designing and analysing joining systems. Therefore, this study aims to establish a probabilistic reliability-based analysis of adhesively bonded FRPs.

The study will address the following objectives:

• Categorise the defects in adhesively bonded joints based on their location: interface, adhesive, and adherends.

• Define the statistical properties of these defects using Uncertainty quantification methods.

• Quantify the presence of defects. There is a need to investigate the influence level and degree of correlation between these different defects and uncertainties using numerical and analytical methods.

• Improve the computational efficiency of the developed stochastic strategy (for example, using a suitable surrogate model).

• Demonstrate the effectiveness of the developed framework in an application case using reliability-based analysis.

• Investigate the possibility of conducting a reliability-based design optimisation for an application case.

For any enquires, feel free to contact Dr Sadik Omairey (sadik.omairey@brunel.ac.uk).

Please note that this position is intended for self-funded PhD students; no funding is currently available to support applicants.

References

The range of uncertainties and defects that this study intends to investigate are available here: https://link.springer.com/article/10.1007/s42452-021-04753-8

How to apply

If you are interested in applying for the above PhD topic please follow the steps below:

1. Contact the supervisor by email or phone to discuss your interest and find out if you would be suitable. Supervisor details can be found on this topic page. The supervisor will guide you in developing the topic-specific research proposal, which will form part of your application.
2. Click on the 'Apply here' button on this page and you will be taken to the relevant PhD course page, where you can apply using an online application.
3. Complete the online application indicating your selected supervisor and include the research proposal for the topic you have selected.

Good luck!

This is a self funded topic

Brunel offers a number of funding options to research students that help cover the cost of their tuition fees, contribute to living expenses or both. See more information here: https://www.brunel.ac.uk/research/Research-degrees/Research-degree-funding. The UK Government is also offering Doctoral Student Loans for eligible students, and there is some funding available through the Research Councils. Many of our international students benefit from funding provided by their governments or employers. Brunel alumni enjoy tuition fee discounts of 15%.

Meet the Supervisor(s)

Sadik Omairey - Sadik is a Research Fellow at Brunel Composites Centre (BCC), a joint venture between Brunel University London and The Welding Institution (TWI) since June 2019. He is currently the technical lead and support for three collaborative projects that involve industrial and academic partners in automotive crash structures design, assembly of an all-composites aircraft fuselage, and thermoplastic additive manufacturing. Besides, Sadik often represents BCC at academic and non-academic conferences and meetings, proposals writings, dissemination, and research papers. While having other duties such as postgraduate students training. Most recently, Sadik achieved PRINCE2® Foundation Project Management certification. Before joining BCC, he was awarded an Elphinstone scholarship from the University of Aberdeen to study a PhD in the reliability and optimisation of composite materials. In 2018, he was recognised as a Chartered Engineer, Member of the Institution of Mechanical Engineers (CEng MIMechE), and a Fellow of the Higher Education Academy (FHEA). Earlier, Sadik completed an MSc degree at the University of South Wales, which was a fully funded scholarship. Whereas his past experience includes industrial positions (oil and gas, and construction). In 2018, Sadik developed EasyPBC tool for homogenisation of composites and hybrid materials. For more details on EasyPBC please visit project's page on ResearchGate from here.

Mihalis Kazilas - Dr Mihalis Kazilas is the Director of the Brunel Composites Centre. He has more than 20 years of experience in the composites processing area. He received his PhD in Advanced Materials from Cranfield University back in 2003. His main field of expertise are polymers characterisation and polymer composites manufacturing and joining processes. He is author of several refereed scientific publications in the area of advanced composites manufacturing and process optimisation. Mihalis is a creative thinker who enjoys problem solving and able to work with different stakeholders to achieve the optimum results in both technical and managerial environments. Work experience:

• Sep 2019 – present: Business Group Manager, Polymer and Composite Technologies, TWI, UK
• June 2019 – present: Director of the Non-Metallics Innovation Centre, a joint initiative between TWI, Saudi Aramco and ADNOC
• Oct 2016 – present: Centre Director, Brunel Composites Innovation Centre, Brunel University London, UK
• Feb 2012 – 2019: Section Manager, Adhesives, Composites and Sealants (ACS) section within the Joining Process Group at TWI, UK
• May 2006 – Jan 2012: R&D Consultant, Project Engineer, Collaborative Projects Operations Manager at INASCO, Greece

Related Research Group(s)

Brunel Composites Centre - Shared research and technology capabilities, specialising in novel composites processing and joining technologies applied to industrial environments.