Author: jo.rich

Freezing Failure: Understanding failure of composites at cryogenic temperatures

Posted on by jo.rich

by David Brearley

The advancements of magnets used in magnetic resonance imaging (MRI) have led to the incorporation of glass fibre reinforced polymer (GFRP) rings being adhesively bonded between epoxy-infused coils of superconducting wire. The two components respond differently to various loading conditions, potentially leading to structural failure. The magnet’s structure is integral to its’ performance as large electromagnetic forces (EMF) are induced due to the strong magnetic field present, under cryogenic temperatures. Unintentional quenches can be triggered by localised heat generated by friction or crack propagation. This results in Ohmic heating, boiling the surrounding liquid helium and potentially causing permanent, catastrophic damage to the magnet.

At the Bristol Composite Institute, the deformation and failure modes of an MRI magnet during operation were investigated by developing an experimental methodology for applying thermomechanical loads to test coupons, effectively mimicking MRI magnets in use. A simple finite element (FE) model of the magnet was constructed to assess the operational stress state and showed that high bi-axial stress concentrations were predicted around the adhesive bond between the coils and GFRP spaces.

To investigate how this could lead to structural failure, a Modified Arcan Fixture (MAF) as shown in Figure 1 was implemented. Several loading hole pairs were used to induce various compression-shear stress states in specimens that contained the adhesive joint cut from a full magnet. In the development of the experimental methodology, a more predictable bonded structure was manufactured using the coil infusion resin as an adhesive to simultaneously evaluate the epoxy’s isolated load response and refine the experiment. Tests were carried out at room and cryogenic temperatures so the thermomechanical load carrying capability of the bond could be evaluated.

Constant cryogenic cooling during quasi-static loading was achieved with the development of a novel modular cryostat that isolates the region around the adhesive bond from the rest of the fixture. The implementation of this cryostat facilitated the use of digital image correlation (DIC) to continually record the specimens’ full field response to the load at cryogenic temperatures, using just boiled pressurized nitrogen as the coolant. Based on a concept from NCC, a rapid prototyping approach was used to iteratively improve the design of the 3D printed cryostat, and in doing so, achieved test temperatures down to -150oC while maintaining the necessary optical clarity.

Figure 1 – Schematic of the Modified Arcan Fixture (left) and the author conducting multi-axial tests with it (right).

This research has improved the understanding of how adhesive bonds, of a similar geometry to those found within an MRI magnet, respond to various bi-axial stress states at room and cryogenic temperatures, see Figure 2. The design process for the developed cryostat opens the door to countless potential possibilities for mechanical testing under cryogenic conditions, where complex thermomechanical stress states require advanced measurement techniques to evaluate the material’s load response.

Figure 2 – Load carrying capability of specimens containing the adhesive bond found within an MRI magnet (circles) and that of adhesively bonded steel plates (crosses, with yield profiles as dotted lines) at ambient (red) and cryogenic (blue) temperatures for various Modified Arcan Fixture load configurations: shear (α=90 ̊), compression-shear at a ratio of 1:2 (α=120 ̊), and of 2:1 (α=150 ̊ )

Composite Process Modelling to Fast-Track the Adoption of New Materials

Posted on by jo.rich

Fibre-reinforced composite manufacturing is highly sensitive to input variability (e.g., fluctuations in areal weight, tow misalignment, or inconsistent binder distribution) [1] which can lead to defects during preforming and subsequent steps. This sensitivity has long hindered the industrial deployment of process models, due to concerns over their predictive accuracy. However, recent work at BCI addresses this challenge by focusing on preforming process modelling, specifically how variations in the architecture and properties of dry textile reinforcements affect fabric deformation during forming. By embedding stochastic material descriptions into finite element forming models, we have demonstrated that it is possible to design robust forming processes that consistently deliver high-quality outcomes even when upstream variability is present [2]. This enables the definition of forming windows that are insensitive to material noise, thereby reducing defect rates and increasing confidence in preform quality. Crucially, one key conclusion from this work is that process models do not need to be perfectly accurate to support optimisation and that capturing the right trends is often enough.

This modelling philosophy becomes even more important when considering sustainable composite systems. In a recently completed PhD project focused on the processing of environmentally friendly materials (i.e., recycled carbon fibres and low-impact resins [3]) we demonstrated that upfront digital design accounting for manufacturing constraints, can significantly accelerate the development of viable processing conditions for new materials (see Figure 1). The same study also confirmed that recycled feedstocks tend to exhibit inherently higher variability. While this challenge remains unresolved for now, it is clear that the modelling strategies developed in the aforementioned study will be valuable here too.

The concept of using physics-based modelling not only to predict outcomes but to enable variability-aware process design will be advanced further in one of the workstreams of a recently announced EPSRC Prosperity Partnership. We strongly believe that wider industrial adoption of new composite systems (which is critical to deliver the net-zero agenda) will not be possible without a much greater reliance on process simulation. This, however, requires a paradigm shift whereby we stop chasing perfect models and start embrace “good enough” models [4].

References:

[1] Chen S., Talokder T., Mahadik Y., Thompson A. J., Hallett S. R. and Belnoue J. P.-H. (2025). Preform variability propagation in non-crimp fabric (NCF) forming, Composites Part B: Engineering, 299:112418, https://doi.org/10.1016/j.compositesb.2025.112418.

[2] Chen S., Thompson A. J., Dodwell T. J., Hallett S. R. and Belnoue J. P.-H. (2025). A comparison between robust design and digital twin approaches for Non-Crimp fabric (NCF) forming, Composites Part A: Applied Science and Manufacturing, 193:108864, https://doi.org/10.1016/j.compositesa.2025.108864.

[3] Yavuz B.O., Hamerton I., Longana M.L. and Belnoue J. P.-H. (2025). Modelling the tensile behaviour of aligned discontinuous carbon fibre thermoplastic matrix composites under processing conditions, Composites Science and Technology, 269:111252, https://doi.org/10.1016/j.compscitech.2025.111252.

[4] Belnoue J. P.-H. and Hallett S. R. (2024). Process models: A cornerstone to composites 4.0, Composites Part B: Engineering, 283:111621, https://doi.org/10.1016/j.compositesb.2024.111621.

Figure 1: Upfront digital design accounting for manufacturing constraint allowed defect-free closed mould forming of 0/90 HiPerDiF carbon fibre/PLA preform. In the baseline case, variability in the preform is responsible for the model to predict preform failure in slightly different places to that in the real preform.

Bristol Composites Institute researchers explore novel joining strategy for modular wind turbine blades

Posted on by jo.rich

Research into novel hybrid joining concepts for segmented composite blades aims to inform the development of modular wind turbine technologies, supporting the industry’s pursuit of larger, more efficient blade design solutions.

As offshore wind turbines grow larger to improve energy capture, the design of wind turbine blades faces mounting challenges. Blade lengths now exceed 100 meters, especially in offshore applications, enhancing energy capture but complicating manufacturing, transport, and assembly. Traditional full-length blade construction is costly and logistically demanding, prompting the industry to explore modular blade designs.

Image showing blade joint concept and stress flow through the joint components across a segmented blade section.

Segmentation of blades, particularly spanwise segmentation i.e. splitting the blade into manageable-sized sections along its length—has emerged as a promising solution to mitigate these challenges. However, re-joining split blade sections while preserving structural integrity and performance comparable to a monolithic blade remains a significant engineering challenge. Existing solutions like mechanical fastening or adhesive bonding offer partial relief but are hindered by trade-offs such as added weight or complex assembly procedures.

To address this challenge, a research team based at the Bristol Composites Institute, University of Bristol, has developed a hybrid adhesive snap-fit joint concept tailored for wind turbine blades. This novel design integrates the alignment and retention features of snap-fit mechanisms with the smooth load transfer capability of adhesive bonding. The resulting joint design is lightweight, scalable, and easier to assemble on site, offering a compelling alternative to conventional joining methods.

This innovative hybrid joint is designed in such a way that the joint components are embedded into the critical load-bearing spar cap region of the blade, where it redirects load paths through the snap-fit joint features while preserving the aerofoil’s outer geometry. Maintaining the external blade profile allows the joint to be incorporated without compromising aerodynamic performance or requiring major design alterations to existing blade moulds, thereby supporting backward compatibility with current manufacturing processes.

Advanced finite element analysis (FEA), incorporating anisotropic composite material models and failure criteria, has demonstrated the joint’s ability to handle extreme load conditions representative of a 10 MW reference blade.  The results showed that the joint can sustain design loads without material failure all while introducing less than 1% additional weight compared to a monolithic blade, representing a significant improvement over conventional joining methods. While further investigation is needed, including prototype building and fatigue loading evaluation, this study represents a significant step toward scalable and manufacturable joint solutions for modular wind turbine blades.

 

Further Information:

The hybrid adhesive snap-fit concept has broader relevance and could inform future joining strategies for composite structures across other engineering applications. Realising its full potential, including prototype development, will require collaborative efforts, and the research team welcomes engagement from industry and academic partners interested in advancing this work toward practical implementation.

Research Team:

Muhammad Basit Ansari, Dr Vincent Maes, Dr Terence Macquart, Dr Eric Kim, Dr Alberto Pirrera To learn more or explore collaboration opportunities, please contact

Muhammad Basit Ansari

basit.ansari@bristol.ac.uk

BCI Alumni Q&A: Steve Grey

Posted on by jo.rich

Why did you choose the Bristol Composites Institute for your studies?
I completed my undergraduate degree in the Aerospace Engineering department at Bristol, so I was already familiar with the research group and their work. I was particularly attracted to the CDT format, which offers the freedom to explore and choose my PhD topic, as well as the opportunity to develop key skills essential for a successful PhD student.

Dr Steve Grey, Lead Satellite Operations Engineer at Space Forge

What research area did you specialise in whilst you were here?
My focus was on engineering origami. Specifically, I was interested in understanding the mechanical properties of origami structures, which theoretically have a single degree of freedom (making them a perfect mechanism), but in reality, they possess multiple degrees of freedom. This means that, while theoretically, a single actuator would suffice to deploy an origami structure, in practice, actuators must be distributed throughout the structure to achieve the desired deployment.

After leaving the BCI where did you go?
My first role after leaving BCI was at a start-up company in Newport called B2Space. This company specialises in high-altitude ballooning, specifically with the objective of creating a satellite launch vehicle that deploys from a high-altitude balloon. Initially, my role was to perform all analyses (structural, aerodynamic, control, etc.) in support of the design of our products. After a few months, I also took over the management of the mechanical design, build, and launch operations of our high-altitude balloons. I spent two years with B2Space, during which I travelled and conducted high-altitude balloon launches in places as diverse as North Wales and the Canary Islands. After those two years, I was ready for a new challenge and moved to Space Forge as the Satellite Operations Lead. In this role, I am responsible for developing and executing the operations of our satellites and payloads throughout their reusable lifecycle. About a year into this role, the opportunity arose to also take on the ForgeStar-1 platform product lead role. As part of this, I am the most senior engineer responsible for the technical decisions throughout the lifecycle of ForgeStar-1 (an R&D satellite), from design through build and test until the mission is complete in orbit.

What are you currently working on and what do your future plans look like?
I am currently preparing to manage the operations of ForgeStar-1 when it launches this summer. My future plans are to grow my team at Space Forge so that we can best support the technology development and design needed to build and operate ForgeStar-2, which will be our first operational satellite performing in-space manufacturing and returning the products to Earth.

How did the BCI prepare you for work outside of academia? 
The two most important things were: 1. Teaching me how to be a self-starter and figure out what the problem is and how to solve it on my own. 2. Giving me the freedom to teach and engage in outreach, which broadened my horizons and helped me make contacts that have been beneficial throughout my subsequent career.

BCI Alumni Q&A: Konstantina Kanari

Posted on by jo.rich

Why did you choose the Bristol Composites Institute for your studies? 
When I was looking for a doctorate, I knew I wanted to work on composite materials but I wasn’t sure about the area in which I wanted to specialise. The CDT programme that BCI offers provided me with the opportunity to learn more about the world of composites before deciding which route interests me the most. Additionally, coming from a science background the CDT provided the opportunity to upskill myself with engineering skills, which is ultimately the route I ended up taking. 

Dr Konstantina Kanari, Advanced Research Engineer, NCC

What research area did you specialise in whilst you were here? 
I worked on the development of nanocomposite materials with enhanced toughness. My research was mostly experimental, using a multi-scale approach to tackle the research question. More specifically, I developed polystyrene nanofibres with embedded cellulose nanocrystals, and then I added these nanofibres as interleaves within composite laminates. I studied the mechanical performance of all the different components, working towards understanding the connection between the properties of the nanofibres and how they affected the mechanical performance of the composite laminates.

After leaving the BCI where did you go?
Initially I moved to Oxfordshire and worked as an R&D Scientist in The Electrospinning Company in the field of biomedical devices. I realised though that the aerospace sector was my true calling, so I returned to Bristol as a Composites Engineer with Alten UK, a consultancy which gave me the opportunity to work for Rolls-Royce and GKN Aerospace. After that, I moved to the National Composites Centre (NCC), where I still work as an Advanced Research Engineer for materials in extreme environments.  

What are you currently working on and what do your future plans look like?
I am currently working on multiple projects on the development of materials and manufacturing processes for materials in extreme environments. That includes materials that can withstand hypersonic speeds, cryogenic environments, and even the synergistic effect of atomic oxygen and radiation in lower earth orbit. In the future I would like to keep working in this area as a technical specialist; the cutting-edge applications that I get to work on are always interesting and they provide an early glimpse into our future! 

How did the BCI prepare you for work outside of academia?
The BCI prepared me by helping me develop both my technical skills, which are of course absolutely necessary, but also my soft skills. Learning how to communicate with your team, how to present your research, how to manage a budget and a timeline… these are qualities that help candidates stand out when applying for jobs, and that eventually make you successful in your career, as you can navigate your projects and any difficulties more easily. 

BCI Alumni Q&A: Laura Veldenz

Posted on by jo.rich

Why did you choose the Bristol Composites Institute for your studies?
I was connected to the former Director Ivana Partridge through one of her former students from Cranfield, he was supervising me during my industry led master thesis. I was invited and coincidentally they had a position that was the perfect topic for me. What really drew me to the EngD programme was the close connection to industry, I had the privilege to work on one of the NCC core projects, sponsored by their Tier 1 partners. This gave me exposure to industry needs, a great industry network and a big challenge to tackle, bridging industry and academia.

Dr Laura Veldenz, Programme Manager, Luchtvaart in Transitie

What research area did you specialise in whilst you were here?
My research area was Automated Fibre Placement with Dry Fibre material. I was able to explore this topic on an industrial level, working with an automation system as it would be used in production, not a small test set up. I was looking into a variety of aspects of this technology, machine parameter determination, influence of part geometries on the layup, the infusion process but also the scalability. I really enjoyed working with a multi-disciplinary team: programmers, metrologists, infusion specialists, production technicians, I have learned so much from all my colleagues.

After leaving the BCI where did you go?
My first job after the EngD was in Sales, which was only short lived. I have learned a lot of what I am not good at and what I do not want to do, which was also a valuable learning experience. I took a different role after less than a year, I joined Airborne in the Netherlands as a proposal engineer, which was a position connecting the sales team and the engineering team. I later changed to the engineering team leading all R&D activities, which brought me back into familiar turf of bridging the gap between research and development. I now work for a Dutch funding body (Luchtvaart in Transitie) overseeing national projects in the aviation sector, working closely with the Dutch government but also the executing companies. Again, I find myself bridging a gap, this time between government and industry.

What are you currently working on and what do your future plans look like?
The funding body Luchtvaart in Transitie is managing several national and international projects, a total of 12 projects, over 60 partners and a budget of several hundred million EUR. I am now overseeing a portfolio of different subsidy projects, branching out from just composites related topics into the broader aerospace industry. I also have responsibilities on the programme management side. I am excited to learn more about the transition to novel propulsion technologies and support the executing parties to develop innovative technology.

How did the BCI prepare you for work outside of academia?
My studies at University of Bristol prepared me in many ways. First of course on a technical level, giving me all the technical knowledge and expertise in the field of composites manufacturing. Perhaps more importantly, I also gained many transferrable skills, such as speaking at conferences, building a strong network, self-confidence, stakeholder management and bridging the gap between industry and academia. Lastly, I learned how important it is to find my passion and to keep going for my goals. I learned that a doctorate is a marathon, not a sprint. This also applies to the career beyond the doctorate, and I am prepared to run the marathon of making aviation sustainable.

Composites Meets Particle Physics at the Forum on Tracking Detector Mechanics

Posted on by jo.rich

On 16th June, in beautiful Bristol sunshine, experts from across the world arrived for the Forum on Tracking Detector Mechanics, co-hosted by Bristol Particle Physics and Bristol Composites Institute.  Particle Physics and Composites might not seem like the most obvious combination- so why spend a week talking about it?

The Compact Muon Solenoid (CMS), photo by CERN

Particle physics experiments such as those in the Large Hadron Collider seek to detect subatomic particles created in high energy collisions.  These experiments involve many layers of detectors around the collision point.  In order to detect and measure the particles as precisely as possible, physicists do not want the support structures, cooling pipes or similar to scatter or absorb them.  This is quantified by the material property radiation length – the average distance of travel by an electron through the material in which the electron energy reduces by a set factor (1/e).  The structures need to have a low material budget (measured as the fraction of a radiation length) while supporting significant load – our composites are perfect for this, particularly carbon fibre reinforced polymer structures.

Diagram showing components of CMS, image by CERN

The collaboration between BCI and CERN began some years ago with a request to help with a challenge.  The detector electronics produce significant heat, so need cooling.  At the moment this is done by pumping coolant through pipes attached to the composite plates the detectors sit on.  In addition to being extra material which might scatter or absorb the particles, these pipes have a different coefficient of thermal expansion to the composite, so when the temperature changes – such as by heating from the detector electronics – pipe and panel expand different amounts, which causes damage and makes the cooling less efficient.  CERN is interested in changing this, instead making integral channels within the composite plate – like the veins of a leaf.  This can be done by including a filament between layers of carbon fibre, which is vaporised off to leave a channel through the composite – but their channels were bursting at far below the target pressure.

My work on the NextCOMP programme provided a possible solution – ‘fuzzy carbon’ micro braids had been used to reinforce pultruded rods for nature-inspired novel composites.  Braiding over the filament before it is integrated into the composite and vaporised results in a reinforced channel – and holds approximately 10 times the pressure.  This collaborative work was funded by the University of Bristol Career Development Fellowship and International Strategic Fund, and led to a discussion regarding a wider collaboration.  A workshop followed – funded by Bristol International Research Collaboration Activities – then we were honoured by a request by the particle physics community to host the Forum on Tracking Detector Mechanics in Bristol, to build better links with our composites community.

We took the opportunity to show off some of the best Bristol has to offer.  The city gave our visitors a glorious welcome with sunshine and balloons during the Welcome drinks at the Sky Lounge atop the Life Sciences building. On the technical side, tours of NCC, Bristol Digital Futures Institute, Bristol Composites Institute and Bristol Particle Physics were well received and led to some fascinating discussions regarding possible future work together.  Could a digital representation of the experimental hardware be helpful in design, maintenance, upgrades?  Will lightweight trusses or tailored fibre placement form the structures of the next generation of particle physics experiments?

Judges inspect some of the posters

Olivia Stodieck of iCOMAT impressed us with a fascinating keynote address about Rapid Tow Shearing and its applications – particle physics experiments may soon be added to the list.  iCOMAT is a spin-out from Bristol Composites Institute commercialising research led by Eric Kim, not only amazing in its own right but also a great example of how our research can get out into the world and change it.

The technical programme included a range of fantastic talks and posters on topics including cryogenics, precision manufacturing, design of lightweight structures, cooling systems and repair when something has gone wrong!  Congratulations to Massimo Angeletti of CERN for the award for best presentation; Cristiano Turrioni of INFN Perrugia and BCI’s David Brearley for the poster prizes.

Group photo at the conference dinner

Our conference dinner at the SS Great Britain was a particular highlight, with a fascinating technical talk regarding Brunel’s famous ship, her many configurations and the conservation process from conservation engineer Nicola Grahamslaw.  Attendees took the chance to explore the ship, observe the balloons flying over and sample some of Bristol’s best pubs afterwards.  Many delighted in the opportunity to find as many Banksys as possible during their time in Bristol, visited the Clifton Suspension bridge and spent time in museums, and we heard plans to come back both for work and pleasure.

Running an international conference is no small feat, so huge thanks to Joel Goldstein, Emma Woodland, Megan Worrall and Robert Oxford Pope, plus everyone who volunteered their time for the tours.  Robert, a CoSEM CDT student, is further developing the work on microvascular channels for detector cooling and is co-supervised by BCI and CERN.

Hypothesis: If you give conference attendees an umbrella, it will be sunny all week

This event demonstrates how a small collaboration can grow and has the potential to become much more.   Bristol Composites Institute and Bristol Particle Physics are both now signed up to a larger international collaboration, coordinated by CERN, to develop the next generation of detector mechanics and we are actively working with partners in the UK and beyond.  The challenges of building tracking detectors are relevant to many other industries – extreme lightweighting, integrated cooling, precision manufacturing, vibration control, materials for extremes of temperature and radiation to name but a few. We are putting together our plans for the collaboration now – this is the time to get involved.

If this is of interest to you, contact Laura.Pickard@Bristol.ac.uk

 

 

 

 

A warm Ghanaian welcome for BCI International Outreach team

Posted on by jo.rich

Testimonial from Mary Sintim Donkor (outreach lead) and the team – Aya Abdo, Nontanasorn (Boss) Budninpech, Ali Kandemir, Robert Oxford Pope, Gökhan Sancak and Anna Williams.  

In February 2025, our team of six students from the EPSRC Centre for Doctoral Training in Composites Science, Engineering and Manufacturing (CoSEM CDT), together with Bristol Composites Institute (BCI) post-doctoral researcher Dr Ali Kandemir, embarked on an international outreach initiative in Ghana. We visited Koforidua Senior High Technical School in Koforidua and the Kwame Nkrumah University of Science and Technology (KNUST) in Kumasi. Our mission was to share knowledge, inspire future engineers, and strengthen collaborations between institutions. This experience proved to be an enriching exchange of ideas and aspirations, leaving a lasting impact on both students and faculty members.

A group of school children standing inside a hall

Engaging with Young Minds at Koforidua Senior High Technical School 

Our outreach officially began at Koforidua Senior High Technical School on Monday 10th February, where we spent the day inspiring students and staff with the wonders of composite materials and manufacturing. However, our mission went beyond technical discussions—it was about empowering the next generation of STEM leaders.

Highlights of the interaction;

  • Inspiration & Motivation – Mary Sintim Donkor kicked off the day by discussing the power of dreams and how to succeed in STEM, reminding students that the sky is the limit.
  • Introduction to Composite Materials – Aya Abdo introduced the fundamentals of composite materials, laying the groundwork for further discussions.
  • Evolution of Materials – Robert Oxford Pope took students on a journey from natural materials to modern applications in composites.
  • Composites in Space – Gökhan Sancak explored the role of composite materials in shaping the future of space exploration.
  • Sustainability Challenges – Dr Ali Kandemir provided insights into the environmental impact of composites and the ongoing efforts to improve their sustainability.
  • Innovative Projects – Anna Williams shared exciting work from the CoSEM CDT22 cohort’s DBT project, showcasing the journey from concept to product development.

The day concluded with an interactive workshop, allowing the high school students to engage directly with our team, ask questions, and explore their ambitions in STEM.

Inspiring the Future of Engineering at KNUST 

Our journey at KNUST began with a tour of the College of Engineering laboratories on Wednesday 12th February, where we gained insights into the cutting-edge research and innovation taking place within the Department of Materials Engineering. This first-hand exposure set the stage for meaningful discussions with students and faculty about advancements in materials science.Two people are stood by a machine place on a table

The second day was packed with engaging sessions and invaluable discussions. We were honoured to receive opening remarks from Professor Albert Adjaottor, setting the tone for the day’s activities including;

  • Presentations by the BCI Outreach Team – Our team introduced students to our research, covering topics such as composite materials sustainability, hydrogen storage, thermal management in particle accelerator detectors, and space environment protection.
  • Diverse Research Perspectives – Alumni speakers George Kwesi Asare, Emmanuella B., Elizabeth Laryea, Paul Sarpong, Joseph Tamirka Bawah, and Ebenezer Acquah shared their experiences and research journeys, providing students with a broader understanding of opportunities within materials science and engineering.
  • Panel Discussion – “Life After Graduation” – Experts including Dr. Frank Agyemang, Dr. Martinson Nartey, Dr. Ali Kandemir, and Gökhan Sancak engaged students in an insightful discussion on navigating career choices and postgraduate studies. A group of people standing in front of a projector screen facing the camera

On Friday 14th February, the outreach wrapped up with practical workshops designed to provide students with hands-on learning experiences.

  • Composite Manufacturing & Testing – A practical session where students engaged with composite material fabrication and evaluation.
  • Graphics & Data Visualisation – Led by Dr. Ali Kandemir, students learned to use Inkscape and QtGrace for scientific design and visualisation.

We concluded the day with an interactive session for teaching assistants, covering graduate school applications, and life in academia. Before departing, we held a heartfelt appreciation session with the Head of Department and faculty members, thanking them for their warm hospitality and support.

A Lasting Impact: Equipment Donation 

One of the major highlights of this outreach was the donation of a mini-injection moulding machine and accessories to the Department of Materials Engineering at KNUST. This equipment, funded by the CoSEM CDT and received by Dr Eric Asare, will provide students with valuable hands-on learning opportunities for years to come.

A Heartfelt Thank You 

This initiative would not have been possible without the dedication and support of many individuals.

At Koforidua Senior High Technical School, we extend our gratitude to Mr Moses Boateng (Coordinator), Mr Ofori Antwi (Headmaster), Mr Bernard Offei Tetteh (Assistant Headmaster, Administration), Mr Lionel Ablordepey (Head of Science), Madam Mercylin Ahenyo (Head of Physics), Mr Samuel Prince Foli (former headmaster) and Chief Prefect Caleb Djormor Yartey and his team.

At KNUST, we appreciate the support of Prof. Emmanuel Gikunoo (HOD), Dr Bennetta Koomson, Dr Eric Asare, Prof. Albert Adjaottor, Dr Frank Agyemang, Dr Martinson Nartey, Emmanuel Kofi Frimpong, Priscilla Fordjour, the volunteer team (Vincent Appiah, Stephen Onomah, Priscilla Mawujorm Korkor, Gracie-Gloria Ahiekpor, Bernard Dzepor, Liza Eshun), and Andrew Senam Newlands Tsini (MATESA President, 2024–2025).

Special thanks to Miss Mary Sintim Donkor for her meticulous planning and to the whole BCI outreach team (Dr. Ali Kandemir, Gökhan Sancak, Anna Williams, Nontanasorn Budninpech, Aya Abo, and Robert Oxford Pope) for making this dream a reality.

We also appreciate the CoSEM CDT Directors (Prof. Stephen Eichorn, Prof. Alberto Pirrera, Prof. Ian Hamerton) and the CoSEM Management Team (Sarah Hallworth, Briony Spraggon, Kathinka Watts, Rebecca FitzHenry) for their unwavering support, coordination, and securing funding through EPSRC. Their contributions were instrumental in the success of this outreach.

This has truly been a journey of endurance, passion, and dedication. We wholeheartedly hope that this interaction continues, leading to more opportunities to engage, collaborate, and inspire. Until next time, Ghana!

The CoSEM CDT welcomes partnerships with individuals or organisations interested in delivering composite outreach activities in Africa and beyond. For further information or to discuss outreach opportunities please contact us on composites-cdt-manager@bristol.ac.uk

 

A collage of 4 photos

PhD research: David Brearley

Posted on by jo.rich

This block, cut from an MRI magnet, consists of an epoxy-infused, insulated copper wire (embedded with filaments of Nb-Ti) spool. The epoxy binds the wires to maintain the structure’s shape, and the copper is used as an electromechanical support for the filaments, which gain superconductive properties when cooled with liquid helium to 4K (-269oC).

The combination of high operational current  (500A, similar to 50 kettles) and a strong magnetic field result in large electromagnetic forces, equivalent to the maximum take-off weight of Boeing 747!

These forces have the potential to cause crack propagation in the epoxy, releasing energy that could significantly increase the local temperature of the wire, meaning it is no longer superconductive. If this happens, the stored current is released, resulting in a rapid chain reaction where the entire magnet undergoes a “quench”.

During the quench, the massive amount of stored electrical energy transforms into heat, causing rapid boil off of the surrounding liquid helium, which is very expensive and, if not vented properly, potentially dangerous to the patient receiving the MRI.

My project aims to get a better understanding of the composite material’s failure initiation, post manufacture, due to operational cryogenic exposure and mechanical loads. My next steps are to examine the combined shear-compression loading effects on the material under cryogenic conditions and use this to inform a model that can predict quench-initiating crack propagation loads.

~ David Brearley, PhD, Aerospace Engineering

Success Through Alignment

Posted on by jo.rich

A test idea was developed into a confirmed proof-of-concept with experimental results in 3 months. We co-created a quick testing method for recycled carbon fibre material, reducing test time from hours to minutes.

Lineat Composites: Lourens Blok, Gary Owen

University of Bristol: Axel Wowogno, Robin Hartley, Benoit Welch, James Kratz

Background

Lineat is a BCI spin-out creating a new recycled carbon fibre material by re-aligning chopped waste fibres into highly aligned fibre tapes that mimic the architecture of virgin continuous fibre materials. The process is well suited to deliver carbon fibre materials circularity needed to meet Net Zero. An Accelerated Knowledge Transfer project was awarded by Innovate UK to evaluate what can be achieved through academic/business collaborations.

Challenge

Short aligned fibre materials can reach similar performance as continuous fibre materials, but it is highly dependent on the level of fibre alignment which can be more variable than long fibre materials. As a consequence, variable fibre orientation may arise leading to reduced volume fraction, leading to undesirable properties. A relatively high compaction force may mitigate some of these issues, but can also be an indicator of alignment quality. In this project, Lineat and Bristol worked together to evaluate if a quick and easy compaction test can reduce cumbersome quality control processes from hours to minutes.

Outcome

Lineat made a selection of recycled short carbon fibre tapes to varying degrees of alignment. The materials were prepared into samples and tested at the University of Bristol to identify the best set-up for a potential quality assurance process. The different test methods were assessed for ease of implementation. The methods were able to successfully discern poorly aligned materials straight away, however, medium and well aligned materials initially seemed similar and required development of an alignment indicator (see Figure 1). Mechanical tests and microstructure observations were used to confirm the alignment results.

 

The project performed three main activities with over 100 experimental tests performed over three months:

1) Develop a compaction test method – A compaction test method was developed and tested at different conditions to indicate alignment.

2) Perform compaction and sample testing –  Once the method was set, the compaction response was measured for different material alignment levels.

3) Correlate properties with fibre alignment – Fibre microstructure and mechanical properties were measured to demonstrate statistical relevance as quality indicator.

Impact

An innovative quality control test to quickly and accurately indicate the level of fibre alignment in recycled short carbon fibre tapes made by Lineat. Initial settings for test sample preparation, testing machine configuration, data analysis instructions, and representative plots for comparison were developed for the business.

Lineat has started an internal project to implement the test method into their production environment and use the testing method to improve manufacturing processes. The outcome is expected to have a significant influence on the uptake of recycled carbon fibre materials.