Development of prototype product print manufacturing capability
Lead Research Organisation:
University of Surrey
Department Name: Mechanical Engineering Sciences
Abstract
The Research will be concerned with developing novel ceramic processing capabilities where manipulation and control at the nano/micro scale has a dramatic impact on the performance of the final product. There exist multiple critical areas (see below) each linked by a common set of materials challenges. Reflecting the dynamic nature of the organisation the themes continually evolve and the research engineer will be expected to contribute to, and help shape the development of, all of them to various degrees with at least one of the areas being their primary area of focus.
Bonding of ceramics to metals
Making a strong mechanical joint between a metal and ceramic is very challenging due to the mismatch between the thermal expansion coefficient between metals and ceramics. A range of processes are possible. Additives in the ceramic sintering process may help. Surface treatments may make adhesion better. Various bonding process could be considered although brazing is currently favoured. This project will look at developing or optimising a joining method for some combinations of materials which appear useful to Dyson. It will also look at characterising the quality of the joint from a thermal and mechanical perspective. Finally we would like to develop a theoretical understanding which underpins experimental findings. In all this, we will need to consider how process could be applied in a manufacturing environment.
Functionalisation of ceramics through doping
Dyson wants to complete an investigation we have already started looking at novel doping combinations to modify the electroceramic and thermo-mechanical properties of a commonly used industrial ceramic. The work will involve preparation of raw ceramics with dopants, characterisation of the green state ceramic, and studying the effect of sintering profiles on the electric and mechanical properties of the sintered piece.
Green state processing for novel geometries
Various methods exist to manipulate ceramics in their green state. Dyson has some unique applications where we seek novel part geometries. We are seeking some ways of forming ceramics into these shapes in the green state. The process must be compatible with the typical mass manufacturing processes for the ceramics we are considering. Considerations of dimension tolerance and mechanical integrity of the final component are important.
The Research Engineer will have a prototyping focus which requires both theoretical and practical knowledge of technical ceramics which serve an electrical, magnetic or dielectric purpose. Home to our global Research, Design and Development centre and all of our Commercial functions, Dyson HQ is tucked away in countryside famous for the railway tunnels and bridges of Isambard Brunel, who revolutionised modern engineering. Our secluded location helps us to protect our ideas and stay independent-minded. Yet nearby are the fashionable cities of Bristol and Bath (where a young James Dyson invented cyclone technology).
Bonding of ceramics to metals
Making a strong mechanical joint between a metal and ceramic is very challenging due to the mismatch between the thermal expansion coefficient between metals and ceramics. A range of processes are possible. Additives in the ceramic sintering process may help. Surface treatments may make adhesion better. Various bonding process could be considered although brazing is currently favoured. This project will look at developing or optimising a joining method for some combinations of materials which appear useful to Dyson. It will also look at characterising the quality of the joint from a thermal and mechanical perspective. Finally we would like to develop a theoretical understanding which underpins experimental findings. In all this, we will need to consider how process could be applied in a manufacturing environment.
Functionalisation of ceramics through doping
Dyson wants to complete an investigation we have already started looking at novel doping combinations to modify the electroceramic and thermo-mechanical properties of a commonly used industrial ceramic. The work will involve preparation of raw ceramics with dopants, characterisation of the green state ceramic, and studying the effect of sintering profiles on the electric and mechanical properties of the sintered piece.
Green state processing for novel geometries
Various methods exist to manipulate ceramics in their green state. Dyson has some unique applications where we seek novel part geometries. We are seeking some ways of forming ceramics into these shapes in the green state. The process must be compatible with the typical mass manufacturing processes for the ceramics we are considering. Considerations of dimension tolerance and mechanical integrity of the final component are important.
The Research Engineer will have a prototyping focus which requires both theoretical and practical knowledge of technical ceramics which serve an electrical, magnetic or dielectric purpose. Home to our global Research, Design and Development centre and all of our Commercial functions, Dyson HQ is tucked away in countryside famous for the railway tunnels and bridges of Isambard Brunel, who revolutionised modern engineering. Our secluded location helps us to protect our ideas and stay independent-minded. Yet nearby are the fashionable cities of Bristol and Bath (where a young James Dyson invented cyclone technology).
People |
ORCID iD |
| Robert Dorey (Primary Supervisor) | |
| Victor Manisa (Student) |
| Description | Characterisation of thermal conductivity of pre-made sintered alumina-CNTs composites using LFA |
| Organisation | National Physical Laboratory |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | I ground off silver electrodes on sintered ceramic pellets using SiC paper and polished samples to be characterised for thermal diffusivity from 25 degC to 500 degC at NPL. The room temperature density of the samples was determined by the Archimedes method. Density as a function of temperature can be determined by correcting the room-temperature density by the thermal expansion. Assuming the CNTs do not affect the thermal expansion coefficient of the composite significantly, density of the CNTs will not change that of alumina significantly hence composite density as a function of temperature was neglected. I visited NPL to observe how the samples were prepared and tested on the LFA-467. NPL sent me the raw thermal diffusivity data which I used to estimate the thermal conductivity of the samples, under the guidance of literature provided by NPL. The literature gave polynomial fits for variation of specific heat capacity (Cp) with temperature for sapphire, graphite and diamond which was used to estimate the Cp for alumina and carbon nanotubes at room temperature and at 500 degC and eventually, that for the composites using rule of mixtures. Rule of mixtures was again used (using mass fractions of the alumina and carbon nanotubes phases) to estimate the thermal conductivity of the samples at the two temperatures using the temperature dependent thermal diffusivity data from NPL, the Cp values I estimated and the temperature independent density determined from the Archimedes method. |
| Collaborator Contribution | NPL provided invaluable thermal analysis experience for this analysis. They did the thermal diffusivity characterisation which took a day per sample as the data was measured over a wide temperature range. They also provided me with the raw data which was also sent in a filtered form easy to use. NPL also provided me with access to the NPL site to see the LFA equipment in use. They also offered guidance on how to estimate the thermal conductivity of the samples using work from literature. |
| Impact | No publications were made from this collaboration. It was more to help introduce me to thermal characterisation techniques that would be fundamental to my research. |
| Start Year | 2018 |
| Description | Pressureless sintering of alumina-carbon nanomaterials at 1400 degC |
| Organisation | University of Manchester |
| Department | School of Materials Manchester |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | I did the green processing to prepare the green bodies that were sintered at University of Manchester. I did green processing which involved making carbon nanotubes and graphene oxide dispersions, milling the different alumina-carbon nanomaterials slurries, drying, and dry milling to obtain the powder. The powder was characterised by TGA, SEM and XRD. The raw carbon nanomaterial powders were characterised by XPS. The milled green powder was then sieved using a designed contained sieving system and pressed into green pellets which were then posted to Manchester University for sintering. I used Archimedes method to determine the density of the sintered pellets. SEM imaging of the sintered pellets showed extremely porous microstructures in both controls and samples with carbon nanotubes, as well as carbon nanomaterials agglomeration. |
| Collaborator Contribution | My contact at the Materials Science Department in Manchester University and their team of technicians/students pressureless sintered my green pellets in an Ar atmosphere at 1400 degC. The control samples looked dense under an optical microscope with no abnormal grain growth while those with carbon nanotube additions showed some delamination. |
| Impact | - The aim of this work was to densify the composites to as high a density as possible using not too expensive sintering technologies hence the use of pressureless sintering as it did not require expensive tooling. - This work provided me with a conclusion that higher sintering temperatures would be needed to densify the composites - Dispersion of the carbon nanotubes also needed to be improved as the agglomerated carbon nanotubes seemed to inhibit densification as reported in literature |
| Start Year | 2018 |
| Description | 23 Things for Research |
| Form Of Engagement Activity | Engagement focused website, blog or social media channel |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Media (as a channel to the public) |
| Results and Impact | The blogging experience I gained from completing 23 Things for Research has been invaluable. It allowed me to talk about my research journey, the challenges, and what tools I could use to make this journey less stressful. I have learnt a great deal about how to work as a researcher. First we learnt how to utilise social media towards improving our profile in the research community. I think the two most important ones (or rather the ones I am using) are LinkedIn and my surrey.ac.uk profiles, with the Surrey one more important if I were to continue in academia as they have the highest search engine optimisation. However I won't have access to my .ac.uk account after university so LinkedIn is my preferred choice. These things also showed me how best to search for information online for example, in Wikipedia, there are links to references in the articles at the bottom of the page and I could follow these links to cite a source because I can't cite Wikipedia. The things also gave good descriptions about using referencing tools and how best to make the most of them. I have been using Mendeley for referencing for 3 years now and I was still able to learn some new features about this tool from 23 Things for Research. One thing I really need to take on is the use of free online courses such as MOOC as these help me develop other skills and makes my profile whether online or CV appears distinct. Presenting research was another topic that was covered, use of tools such as Prezi and Slideshare was described in detail. These will probably be suited to making presentations to my company managers so it is something I intend to use at some point. I could also use these data presentation skills for some of the Elective Activities of the Communications Portfolio. Working as a RE, I need quick access to articles when doing literature search. Sometimes it's really annoying when you're searching for information and you can't access it because of a need to pay subscription fees. One of things talked about Open access and how it is important to the research community. In a perfect world, access to all research should be free and, it should not take a 6 month embargo period upon publishing in a journal for the paper to be accessible. Open access helps to maximise the impact of research so it is paramount that stakeholders involved should implement policies that allow for this to work. Through 23 Things, I've also learnt of the various funding sources available to me so I'll use these in future when applying for extra funding for attending conferences or doing collaboration work with local or international researchers. |
| Year(s) Of Engagement Activity | 2018 |
| URL | https://electroceramic.wordpress.com/ |
| Description | THE BIG DROP SUMMER SCHOOL OUTREACH PROJECT |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Schools |
| Results and Impact | THE BIG DROP SUMMER SCHOOL OUTREACH PROJECT Over 16 hours from Monday 9th of July until Friday 13th of July, I mentored (with 6 other REs) 12 A-level students on this activity where they had to safely transport a payload (USB/DTU-data transfer unit) over 100m using a water/CO2 pressurised rocket. The DTU recorded some parameters such as force on impact, distances travelled etc and these were plotted on excel. The students were split into two teams and within each team, they had to come up with two design solutions which were tested on the field later on in the week. This was like a research project so the approach we encouraged the students to approach was solve this design problem like doing research i.e think about the problem, brainstorm ideas and research possible solutions, test the hypothesis, review, iterate solutions, test them and then choose a final solution. During testing, the students had to note down any observations to help them with the results analysis later. Finally, from the two designs in each team, the students chose their final solution and then made a power point presentation about how they reached their conclusion. Project Aims and Objectives To provide a broad educational project in Mechanical/Aerospace Engineering that:- * Develops the knowledge, understanding, practical and inter-personal skills so as to prepare the project attendees for a career as professional engineers and scientists in industry, the public services and the academic world. * Incorporates a real life engineering problem based in Mechanical/Aerospace engineering topics. * Provides a deepening and broadening in both theory and application of engineering and teamwork skills. Learning Outcomes Knowledge and Understanding of: * A range of mathematical & computer methods relevant to Mechanical/ Aerospace * A range of scientific principles, methodologies & emerging concepts applied to Mechanical/ Aerospace and related engineering disciplines * A range of engineering design processes & of customer needs * A range of engineering materials & components * A range of management and business practices * The practice of design, manufacture and evaluation * Information sources & intellectual property * Health & safety, environmental & sustainability considerations * How to apply & integrate knowledge from other disciplines to the field of Mechanical/ Aerospace Engineering Cognitive skills leading them to be able to: * Appreciate the contexts in which engineering knowledge can be applied * Select and apply appropriate mathematical & engineering principles * Develop engineering solutions to practical problems * Analyse systems and synthesise solutions using a systems approach * Plan and manage complex projects * Work with technical uncertainty Practical skills leading them to be able to: * Apply appropriate mathematical methods * Demonstrate competence in laboratory and workshop practice * Demonstrate familiarity with IT and computing tools related to mechanical engineering * Conduct the design process from concept to product including technical analysis and critical analysis of outcomes * Research information to develop ideas * Use research methods to conduct an individual project Key transferable skills leading them to be able to: * Use of scientific evidence and logical thought in the presentation of ideas * Evaluate information and requirements * Use creativity and innovation in problem solving * Effectively communicate using oral and written skills * Manage time effectively * Lead and be part of a technical team * Use common IT and computing resources to present reports and data The project was outlined as follows: 1. All REs mentors had a 1.5 hr training session with Phil (project leader) prior to the project start, where we discussed the project details, possible difficulties that may arise or questions the students may pose, solutions or how to deal with a situation such as a particular student not getting involved as much as others (encourage the students and get them thinking about problems instead of just giving them solutions). Before the start of each session during the week, all mentors arrived 30 mins prior to the students arriving to prepare the room, materials and discuss potential questions. After each session, we stayed for a further 20-30 mins wrapping up the day to discuss issues that came up, and just clearing up the room 2. On day 1, there was an Introduction to studying Engineering at University of Surrey presentation by Phil and then the mentors (REs) introduced the project to the students, answering any questions they had. Grouped the students into two teams. Within these teams, we got the students to start conceptualising potential solutions and discussing them. They then started to research/design possible solutions for the project and, we advised they have multiple designs so they have a big pool from which to choose their two final designs. We encouraged the students to make sketches so they could visualise their solutions. The students decided on using a crumple zone and a parachute. 3. On day 2, we briefed the students about plans for the day. Using the two designs, we guided the students by making them have a think how each structure would be built, why a particular shape was chosen for the design and then have a think about materials selection: the main aim was to protect the DTU from damage on impact so, what sort of materials could be used to absorb impact and most importantly, how these would be built into a structure most suitable for protecting the DTU yet not compromising the path of the rocket during flight. The students created an initial design which was dropped from a height for the first test without the DTU in the capsule design. On assessing the damage, we sort of wanted the students to think why the design failed, take pictures for the presentation and then propose ways of minimising this damage. The students then had to amend and create an iteration of the initial capsule design and manufacture the final design. The students started preparing for the presentation by collecting all the data/pictures they had and started writing 4. On day 3 + 4, the students completed their final designs and then the capsule designs were each Flight tested with the DTU in place. Before the flight test, we had to brief the teams about safety and provided them with goggles. The DTU had G-force sensors and the data acquired after each flight test was plotted on excel. The students took this data, together with the pictures/videos taken during the rocket flight, to analyse and discuss any damage on the capsules and try to link this to the DTU G-force data. The students continued working on their power point presentations and we advised them on how to make an interesting presentation. We made sure every student had a part to talk about during the 10 minutes presentation the next day. We encouraged the students to practise their presentations and based on the results of the Flight test, choose one capsule design from each team as part of their conclusion. 5. On day 5, the students gave 10 minute presentations to Civil Engineering Research Project attendees and we gave them feedback. They also provided us with feedback. The feedback received from the students in attendance said they had the most amazing time and will be applying what they learned to their future studies The outreach project was well planned, much organised with every session ending on time. The students seemed enthusiastic about the work and we tried to get everyone as much as involved as we could. For future improvements, maybe we could add some added difficulty. What I mean by that is that we propose an extra activity on top of this work so that whichever team completes their work first, could do it and gain extra points (like a bonus activity). Reason I'm saying this is because some of the students sort of looked a bit bored at times during the week so maybe they weren't challenged enough. Also, we could get DTUs that can get more than one data set type i.e measure other parameters such as air resistance etc (might be expensive though) so that the students have more data to fiddle with and maybe give them a realistic feel about what sort of data types they'd have to deal with when studying engineering at university |
| Year(s) Of Engagement Activity | 2018 |