Advanced Manufacturing of Through-Thickness Reinforced Composites

This PhD project aims to address one of the biggest weaknesses for fibre reinforced composites, i.e. their relatively weaker out-of-plane properties compared to in-plane properties, by developing an advanced through-thickness reinforcement (TTR) manufacturing process. The novel manufacturing process allows embedding through-thickness reinforcement in composites with minimal damage to TTR and composites themselves. This PhD project will be undertaken in an active composite group affiliated with the world-class Institute of Design, Robotics and Manufacturing (iDRaM) at the School of Mechanical Engineering, University of Leeds. This PhD project presents a distinctive opportunity for the successful candidate to specialise in composites and manufacturing. Apart from researchers in the Institute, School and University, the PhD student will also have plenty of opportunities to intensively interacting with our industry partners in the areas of aerospace, energy, healthcare and automotive to facilitate the real-world applicability of their research findings. The PhD student is expected to publish high-quality papers on high-profile international journals, and disseminate research outcomes at national and international conferences, workshops and seminars.

<h4 paraeid="{dd041517-03b9-4116-9ad6-750dd62b7068}{33}" paraid="1657558327"><strong>Project background:  </strong></h4> <p>Fiber-reinforced composites are increasingly used across various engineering sectors as they are strong and lightweight, e.g. aerospace, automotive, renewable energy and sport. Numerous modern engineering products prominently feature composites, including A350 and Boeing 787 aircrafts, the new generation of Rolls-Royce and General Electric aero engine fan blades, and the long-span wind turbine blades manufactured by Siemens and Vestas. Additionally, composites are increasingly utilised in electric vehicles to increase power density.  </p> <p>Fiber-reinforced composite structures are typically fabricated by layering reinforcement materials, such as carbon or glass fibres, in the thickness direction. Matrix materials, like resin, are then applied to impregnate the reinforcement, either before or after layup. Heat and pressure are applied to consolidate the entire assembly of fibres and matrix to removing voids and volatiles and achieving the desired fibre volume fractions and dimensional tolerances. However, one drawback is the lack of reinforcement in the thickness direction. Thus, composites have relatively weaker out-of-plane properties compared to in-plane properties, and they are susceptible to debonding between plies. To overcome this limitation, various through-thickness reinforcement techniques have been developed, including tufting, Z-pinning and stitching, to introduce reinforcement phase through the thickness of composites. This PhD project aim to advance the TTR technique by developing an advanced manufacturing process that allows embedding through-thickness reinforcement in composites with minimal damage to TTR and composites themselves. </p> <p paraeid="{dd041517-03b9-4116-9ad6-750dd62b7068}{39}" paraid="1811087557"><strong>References </strong></p> <p paraeid="{dd041517-03b9-4116-9ad6-750dd62b7068}{85}" paraid="532209200">Partridge, I. K. and Hallett, S. R. (2016) ‘Use of microfasteners to produce damage tolerant composite structures’, Philosophical Transactions of the Royal Society A, 374(2071). </p> <p paraeid="{dd041517-03b9-4116-9ad6-750dd62b7068}{95}" paraid="892994484">Mouritz, A. P. (2020) ‘Review of z-pinned laminates and sandwich composites’, Composites Part A: Applied Science and Manufacturing, 139(September), p. 106128.  </p> <p paraeid="{dd041517-03b9-4116-9ad6-750dd62b7068}{101}" paraid="367179966">Zhang, B., Hallett, S. R. and Allegri, G. (2022) ‘Sensing delamination in composites reinforced by ferromagnetic Z-pins via electromagnetic induction’, Composites Science and Technology, 217(October 2021), p. 109113.  </p> <p paraeid="{dd041517-03b9-4116-9ad6-750dd62b7068}{107}" paraid="666676315">Zhang, B. et al. (2015) ‘Micro-mechanical finite element analysis of Z-pins under mixed-mode loading’, Composites Part A: Applied Science and Manufacturing, 78, pp. 424–435.  </p> <p paraeid="{dd041517-03b9-4116-9ad6-750dd62b7068}{113}" paraid="435903426">Zhang, B., Allegri, G. and Hallett, S. R. (2016) ‘An experimental investigation into multi-functional Z-pinned composite laminates’, Materials & Design, 108, pp. 679–688.  </p> <p paraeid="{dd041517-03b9-4116-9ad6-750dd62b7068}{119}" paraid="586663738">Verma, K. K. et al. (2019) ‘The key role of thread and needle selection towards “through-thickness reinforcement” in tufted carbon fiber-epoxy laminates’, Composites Part B: Engineering, 174, p. 106970.  </p>

<p>Formal applications for research degree study should be made online through the <a href="https://www.leeds.ac.uk/research-applying/doc/applying-research-degrees">University's website</a>. Please state clearly in the Planned Course of Study section that you are applying for <em><strong>PHD Mechanical Engineering FT</strong></em>, in the research information section that the research degree you wish to be considered for is <em><strong>Advanced Manufacturing of Through-Thickness Reinforced Composites</strong></em> as well as <a href="https://eps.leeds.ac.uk/staff/14360/dr-bing-zhang">Dr Bing Zhang</a> as your proposed supervisor and in the finance section, please state clearly <em><strong>the funding that you are applying for, if you are self-funding or externally sponsored</strong></em>.</p> <p>If English is not your first language, you must provide evidence that you meet the University's minimum English language requirements (below).</p> <p><em>As an international research-intensive university, we welcome students from all walks of life and from across the world. We foster an inclusive environment where all can flourish and prosper, and we are proud of our strong commitment to student education. Across all Faculties we are dedicated to diversifying our community and we welcome the unique contributions that individuals can bring, and particularly encourage applications from, but not limited to Black, Asian, people who belong to a minority ethnic community, people who identify as LGBT+ and people with disabilities. Applicants will always be selected based on merit and ability.</em></p> <p class="MsoNoSpacing" style="text-align:start; margin-bottom:24px">Applications will be considered on an ongoing basis.  Potential applicants are strongly encouraged to contact the supervisors for an informal discussion before making a formal application.  We also advise that you apply at the earliest opportunity as the application and selection process may close early, should we receive a sufficient number of applications or that a suitable candidate is appointed.</p> <p style="margin-bottom:11px"><strong>Please note that you must provide the following documents in support of your application by the closing date of Monday 6 January 2025 if applying for the China Scholarship Council-University of Leeds Scholarship, Monday 3 February 2025 if applying for Leeds Doctoral Scholarship or Tuesday 1 April 2025 for Leeds Opportunity Research Scholarship.</strong></p> <p>If you are applying with external sponsorship or you are funding your own study, please ensure you provide your supporting documents at the point you submit your application:</p> <ul> <li>Full Transcripts of all degree study or if in final year of study, full transcripts to date</li> <li>Personal Statement outlining your interest in the project</li> <li>CV</li> </ul>

Applicants to research degree programmes should normally have at least a first class or an upper second class British Bachelors Honours degree (or equivalent) in an appropriate discipline. The criteria for entry for some research degrees may be higher, for example, several faculties, also require a Masters degree. Applicants are advised to check with the relevant School prior to making an application. Applicants who are uncertain about the requirements for a particular research degree are advised to contact the School or Graduate School prior to making an application.

The minimum English language entry requirement for research postgraduate research study is an IELTS of 6.0 overall with at least 5.5 in each component (reading, writing, listening and speaking) or equivalent. The test must be dated within two years of the start date of the course in order to be valid. Some schools and faculties have a higher requirement.

<p style="margin-bottom:12px"><strong>Self-Funded or externally sponsored students are welcome to apply.</strong></p> <p><strong>UK</strong> – The <a href="https://phd.leeds.ac.uk/funding/138-leeds-doctoral-scholarship-2025-faculty-of-engineering-and-physical-sciences#:~:text=Key%20facts&text=One%20Leeds%20Doctoral%20Scholarship%20is,rata%20for%20part%2Dtime%20study.">Leeds Doctoral Scholarships</a> <strong>(closing date: Monday 3 February 2025)</strong> and <a href="https://phd.leeds.ac.uk/funding/234-leeds-opportunity-research-scholarship-2022">Leeds Opportunity Research Scholarship</a> <strong>(closing date: Tuesday 1 April 2025)</strong> are available to UK applicants. <a href="https://phd.leeds.ac.uk/funding/60-alumni-bursary">Alumni Bursary</a> is available to graduates of the University of Leeds.</p> <p><strong>Non-UK</strong> – The <a href="https://phd.leeds.ac.uk/funding/48-china-scholarship-council-university-of-leeds-scholarships-2021">China Scholarship Council - University of Leeds Scholarship</a> is available to nationals of China <strong>(closing date: Monday 6 January 2025)</strong>. The <a href="https://phd.leeds.ac.uk/funding/73-leeds-marshall-scholarship">Leeds Marshall Scholarship</a> is available to support US citizens. <a href="https://phd.leeds.ac.uk/funding/60-alumni-bursary">Alumni Bursary</a> is available to graduates of the University of Leeds.</p> <p><strong>Important: </strong>Please note that that the award does <em><strong>not</strong></em> cover the costs associated with moving to the UK.  All such costs (<a href="https://www.leeds.ac.uk/international-visas-immigration/doc/applying-student-visa">visa, Immigration Health Surcharge</a>, flights etc) would have to be met by yourself, or you will need to find an alternative funding source. </p> <p>Please refer to the <a href="https://www.ukcisa.org.uk/">UKCISA</a> website for information regarding Fee Status for Non-UK Nationals.</p>

<p>For further information about this project, please contact Dr Bing Zhang by email to <a href="mailto:B.Zhang2@leeds.ac.uk">B.Zhang2@leeds.ac.uk</a></p> <p>For further information about your application, please contact PGR Admissions by email to <a href="mailto:phd@engineering.leeds.ac.uk">phd@engineering.leeds.ac.uk</a><br />  </p>