The University of Sheffield

<p><strong>Overview:</strong></p>
<p>The University of Sheffield is a world top-100 university renowned for the excellence, impact and distinctiveness of its research-led learning and teaching. The University’s outstanding performance for excellent teaching and research, as part of a genuinely global community, is consistently confirmed by international independent assessments.</p>
<p>The university takes its public and social responsibility seriously. It is committed to making the world a better place. This approach is embedded in everything they do, from partnerships with local and global organisations to their research and teaching.</p>
<p><strong>Research:</strong></p>
<p>The University of Sheffield has a global reputation for world-leading research that makes a difference. It influences policy, changes lives and helps in understanding the world so that we can make it better. The university has over 180 research institutes, centres and groups. They address challenges from finding a cure for motor neurone disease to building a sustainable economic recovery. The research institutes and centres at the university have been created to address global challenges facing society, today and in the future. They are often interdisciplinary, with external collaboration and funding, and have earned international recognition.</p>
<p>The world-class research being undertaken at the University of Sheffield generates a wealth of new knowledge, much of which has the potential for licensing to innovative organisations seeking to augment their current activities or diversify their operations.</p>
<p><strong>Industry Partnerships:</strong></p>
<p>The University of Sheffield is collaborating with partners in the private, public and third sectors to find real-world solutions to real-world problems.</p>
<p>The university partners with organisations large and small, believing that by working together, we can find novel solutions to real-world problems. In their experience, it leads to world-class research and commercial success to businesses around the world. Together, The University of Sheffield shares knowledge, facilities and industry insight to help influence cultural, social, economic and political change.</p>


<h1 id="background">Background</h1>
<p>For maximum mechanical performance, composite materials must be cured at high temperatures. For manufacturers, this process is energy-intensive and uses expensive equipment such as an autoclave or oven. Rapid heating reduces time and energy use but risks triggering a runaway exothermic reaction. Such inherent overheating results in scrapped parts, damage to equipment or even fire. For a large, high lag system, applying too much power at the wrong time in the cycle may make an exotherm unavoidable, but that may not actually become apparent for up to 30 minutes at which point it is too late to avoid. As a result, composite curing processes are highly conservative, using very slow heating rates and long isothermal dwells.</p>
<p>The University of Sheffield’s Advanced Manufacturing Research Centre (AMRC) researchers have developed a code (CureAll) which controls the curing process based on a prediction of its future state, allowing the temperature profile to run as close as possible to the exothermic limit without ever exceeding it.</p>
<h1 id="technology-overview">Technology Overview</h1>
<p>The CureAll code is a package of Python objects and functions which analyse both the composite material and its surrounding system, fitting a large set of parameters. This parameterisation allows the code to make predictions of the future effects of control inputs. The code has been validated for real-time control of cures on the oven and heated tooling equipment.</p>
<p>The solution can be used offline, to simulate pre-cure or to review data post-cure, or it can be used online, to provide real-time control.</p>
<h1 id="benefits">Benefits</h1>
<ul>
<li>CureAll saves time and energy by allowing rapid heating without the risk of triggering a runaway exotherm. An aerospace-grade carbon fibre pre-preg panel which (would normally take 5 hours 30 minutes to cure) was cured in 1 hour 15 minutes, saving 78% of the cure time and 46% of the energy.</li>
<li>Part quality maintained or even improved. In the above work, the void content was lower and the interlaminar shear strength and glass transition temperature of the panel were higher for the more rapidly cured part than the part cured in a conventional way.</li>
<li>The parameterisation of material and system are automatable and variations in the parameters could provide a further metric for quality control.</li>
<li>Hardware is agnostic. Inputs can be thermocouples, Resistance Temperature Detectors (RTD) or dielectric sensors. Outputs can be used to control ovens, autoclaves, heated presses, heated tooling or microwave, resistive or inductive heating.</li>
</ul>
<p>In order to safely run close to exothermic limits on high lag equipment, a predictive system such as CureAll is essential.</p>
<h1 id="applications">Applications</h1>
<p>The code is currently tailored to the needs of curing high-temperature epoxy resin-based materials. These are typically used in the aerospace sector although are increasingly being applied in automotive and renewable energy. The code can also be developed for other chemistries.</p>
<h1 id="opportunity">Opportunity</h1>
<p>Software development and distribution partner.</p>
