Composites are truly the materials of the future, due to their excellent properties such as high strength to weight ratio, and their use is rising exponentially, continuing to replace or augment traditional materials in different sectors such as aerospace, automotive, wind turbine blades, civil engineering infrastructure and sporting goods. A good example is the construction of large aircraft such as the Airbus A350 and Boeing 787 which are 53% and 50% composite by weight, respectively. However, while the fibre dominant properties guarantee excellent in-plane load-bearing characteristics, traditional composite materials exhibit weak resistance to out-of-plane loads, making them susceptible to barely visible impact damage (BVID) under impact loads that can happen during manufacturing or in service. BVID can drastically reduce the strength, without any visible warning. Structures that look fine can fail suddenly at loads much lower than expected. This weak impact resistance together with the complexity of the failure mechanisms typical of composite systems led in the past decade to complex and expensive maintenance/inspection procedures. Therefore, a significantly greater safety margin than other materials leads to conservative design in composite structures. Based on these premises, the need is clear for a comprehensive solution that matches the requirements of lightweight structures with the need for high impact resistance and ease of inspection. This project is aimed at the design and development of next generation of high-performance impact resistant composites with visibility of damage and improved compression after impact strength. These exceptional properties are caused with ability to visualise and control failure modes to happen in an optimised way. Energy would be absorbed by gradual and sacrificial damage, strength would be maintained, and there would be visible evidence of damage. This would eliminate the need for very low design strains to cater for BVID, providing a step change in composite performance, leading to greater reliability and safety, together with reduced design and maintenance requirements, and longer service life. This is an exciting opportunity to develop this novel proposed technology with my extensive industrial partners, a potentially transformative prospect for the UK composites research and industry.

Composites are truly the materials of the future, due to their excellent properties such as high strength to weight ratio, and their use is rising exponentially, continuing to replace or augment traditional materials in different sectors such as aerospace, automotive, wind turbine blades, civil engineering infrastructure and sporting goods. A good example is the construction of large aircraft such as the Airbus A350 and Boeing 787 which are 53% and 50% composite by weight, respectively. However, while the fibre dominant properties guarantee excellent in-plane load-bearing characteristics, traditional composite materials exhibit weak resistance to out-of-plane loads, making them susceptible to barely visible impact damage (BVID) under impact loads that can happen during manufacturing or in service. BVID can drastically reduce the strength, without any visible warning. Structures that look fine can fail suddenly at loads much lower than expected. This weak impact resistance together with the complexity of the failure mechanisms typical of composite systems led in the past decade to complex and expensive maintenance/inspection procedures. Therefore, a significantly greater safety margin than other materials leads to conservative design in composite structures. Based on these premises, the need is clear for a comprehensive solution that matches the requirements of lightweight structures with the need for high impact resistance and ease of inspection. This project is aimed at the design and development of next generation of high-performance impact resistant composites with visibility of damage and improved compression after impact strength. These exceptional properties are caused with ability to visualise and control failure modes to happen in an optimised way. Energy would be absorbed by gradual and sacrificial damage, strength would be maintained, and there would be visible evidence of damage. This would eliminate the need for very low design strains to cater for BVID, providing a step change in composite performance, leading to greater reliability and safety, together with reduced design and maintenance requirements, and longer service life. This is an exciting opportunity to develop this novel proposed technology with my extensive industrial partners, a potentially transformative prospect for the UK composites research and industry.

Standard multi-kW fibre lasers are now considered 'commodity' routinely produced by multiple manufacturers worldwide and are widely used in the most advanced production lines for cutting, welding, 3D printing and marking a myriad of materials from glass to steel. The ability to precisely control the properties of the output laser beam and to focus it on the workpiece makes high-power fibre lasers (HPFLs) indispensable to transform manufacturing through adaptable digital technologies. As we enter the Digital Manufacturing/Industry 4.0 era, new challenges and opportunities for HPFLs are emerging. Modern product life-cycles have never been shorter, requiring increased manufacturing flexibility. With disruptive technologies like additive manufacturing moving into the mainstream, and traditional subtractive techniques requiring new degrees of freedom and accuracy, we expect to move away from fixed, 'fit-for-all' beams to 'on-the-flight' dynamically reconfigurable 'shaped light' with extensive range of beam shapes, shape frequency and sequencing, as well as 3D focus steering. It is also conceivable that the future factory floor will get 'smarter', undergoing a rapid evolution from dedicated static laser stations to robotic flexible/reconfigurable floorplans, which will require 'smart photon delivery' over long distances to the workpiece. Such a disruptive transition requires a new advanced generation of flexible laser tools suitable for the upcoming 4th industrial revolution. Light has four characteristic properties, namely wavelength, polarization, intensity, and phase. In addition, use of optical fibres enables accurate control and shaping in the spatial domain through a variety of well-guided modes. Invariably, all photonic devices function by manipulating some of these properties. Despite their acclaimed success, so far HPFLs are used rather primitively as single-channel, single colour, mostly unpolarised and unshaped, raw power providers and remain at a relatively early stage (stage I) of their potential for massive scalability and functionality. Moreover, further progress in fibre laser power scaling, beam stability and efficiency is hindered by the onset of deleterious nonlinearities. On the other hand, the other unique attributes, such as extended 'colour palette', extensively controllable polarisation and beam shaping on demand, as well as massive 'parallelism' through accurate phase control remain largely unexplored. Use of these characteristics is inherent and comes natural to fibre technology and can add unprecedented functionality to a next generation of 'smart photon engines' and 'smart photon pipes' in a stage II of development. This PG will address the stage II challenges, confront the science and technology roadblocks, seek innovative solutions, and unleash the full potential of HPFLs as advanced manufacturing tools. Our aim is to revolutionise manufacturing by developing the next generation of reconfigurable, scalable, resilient, power efficient, disruptive 'smart' fibre laser tools for the upcoming Digital Manufacturing era. Research for the next generation of manufacturing tools, like in HiPPo PG, that will drive economic growth should start now to make the UK global leaders in agile laser manufacturing - enabling sustainable, resource efficient high-value manufacturing across sectors from aerospace, to food, to medtech devices and automotive. In this way the UK can repatriate manufacturing, rebalance the economy, create high added-value jobs, and promote the green agenda through efficient manufacturing. It will also enhance our defence sovereign capability, as identified by the Prime Minister in the Integrated Review statement to the House of Commons in November 2020.

The chemical and pharmaceutical industries are currently reliant on petrochemical derived intermediates for the synthesis of a wide range of valuable chemicals, materials and medicines. Decreasing petrochemical reserves, and concerns over increasing cost and greenhouse gas emissions, are now driving the search for renewable and environmentally friendly sources of these critically needed compounds. This project aims to establish a range of new manufacturing technologies for efficient conversion of biomass in agricultural waste streams into sustainable sources of these valuable chemical intermediates. The UK Committee on Climate Change (2018) has highlighted the importance of the efficient use of agricultural biomass in tackling climate change. The work undertaken in this project will contribute to this effort and help the UK government achieve its stated target of 'net-zero emissions' by 2050. The new approaches will be exemplified using UK-sourced Sugar Beet Pulp (SBP) a renewable resource in which the UK is self-sufficient. Over 8 million tonnes of sugar beet is grown annually in the UK on over 3500 farms concentrated in East Anglia and the East Midlands. After harvest, the beet is transported to a small number of advanced biorefineries to extract the main product; the sucrose we find in table sugar. SBP is the lignocellulosic material left after sucrose extraction. Currently it is dried (requiring energy input) and then sold as a low-value animal feed. SBP is primarily composed of two, naturally occurring, biological polymers; cellulose and pectin. Efficient utilisation of this biomass waste stream demands that applications are found for both of these. This work will establish the use of the cellulose nanofibres for making antimicrobial coatings and 3D-printed scaffolds (in which cells can be cultured for tissue engineering and regenerative medicine applications). The pectin will be broken down into its two main components: L-arabinose and D-galacturonic acid. The L-arabinose can be used directly as a low-calorie sweetener to combat the growing problem of obesity. The D-galacturonic acid will be modified in order to allow formation of biodegradable polymers which have a wide range of applications. This new ability to convert SBP into a range of useful food, chemical and healthcare products is expected to bring significant social, economic and environmental benefits. In conducting this research we will adopt a holistic approach to the design of integrated biorefineries in which these new technologies will be implemented. Computer-based modelling tools will be used to assess the efficiency of raw material, water and energy utilisation. Techno-Economic Analysis (TEA) and Life Cycle Analysis (LCA) approaches will be employed to identify the most cost-effective and environmentally benign product and process combinations for potential commercialisation. The results will be widely disseminated to facilitate public engagement with the research and ethical evaluation. In this way the work will support the UK in its transition to a low-carbon, bio-based circular economy.

HetSys students will develop and apply computational models for heterogeneous material systems, addressing three distinct but closely connected shortcomings in current modelling paradigms: (i) most material systems of scientific and technological interest are highly heterogeneous in structure, phases, and range of length- and time-scales, whereas the predominant modelling paradigms typically focus on limited scenarios; (ii) coupling of scales is typically ad hoc, thus lacking robust quantification of uncertainty propagation across scales, essential for reliable and applicable models; (iii) research software is often poorly maintained and hard to re-use, further slowing down progress. Overcoming these interdisciplinary challenges to unlock more efficient simulation-for-design capabilities has been hindered by outdated training approaches: the pathway followed by, for example, a theoretical physicist has been distinct from that of a materials engineer, with the resulting lack of a 'common language' preventing synergy across disciplines. HetSys will transform this landscape by being the first CDT explicitly targeting modelling of heterogeneous systems required by industry and academia, with all models to be implemented in robust and reusable software that produces probabilistic error bars on all outputs using uncertainty quantification (UQ). Exemplar research challenges range from novel materials and devices exploiting multiscale physics and chemistry, high performance alloys, direct drive laser fusion, future medicine exploration, smart nanofluidic interfaces, and flow through heterogeneous rocks. HetSys' mission is to train high-quality computational scientists who can develop and implement new methods for modelling complex and heterogeneous systems in collaboration with scientists and end-users. Working in a highly interdisciplinary context is challenging even for experienced researchers but especially for an isolated PhD student. Creating a cohesive, interdisciplinary cohort connected through a joint training programme with an existing vibrant cross-departmental research community will create a culture that significantly lowers the entrance barrier into this style of research. Our multidisciplinary approach aligns with the formation of UKRI and will help to address the productivity gap identified in the industrial strategy by targeting several challenges and national priority areas. As noted by Innovate UK/KTN: "Industry requires new insight into how [materials] behave and uniquely this proposal sets the understanding of how uncertainty propagates across scales as a central theme". These benefits are recognised by industry through HetSys' strong support from 14 industrial project partners. We have also established bilateral links with 12 international partners who have identified the same urgent modelling challenges. The potential impact of the postgraduate training is affirmed by the career destinations of the 70 students who completed their studies with the 33 HetSys supervisors since 2012: 27 have proceeded into academic research (21 postdoctoral and 6 academic posts), 28 into careers in industrial R&D and the engineering industry, 4 into IT, 2 to consultancy, 6 into school teaching and 2 to finance. The strong absorptive capacity for graduates is recognised by project partners, e.g. AWE: "given the ever growing importance that computational modelling is acquiring in the UK and internationally, there will be significant competition for the number of doctoral level scientists and engineers that you are proposing to train". New paradigms in the study of heterogeneous materials are vital for both academic research and industry. Future impact at larger scales will be greatly increased if researchers can be trained to master a wide range of techniques and encapsulate them in well-designed software.