8 research outputs found

    Micro injection moulding: tooling and process factors

    Get PDF
    The development of new micro devices is highly dependent on manufacturing systems that can reliably and economically produce micro components in large quantities. Micro injection moulding is one of the key technologies for micro-manufacture and is considered as a cost effective replication method for mass production. The capabilities of this replication technology have to be studied systematically in order to determine the process constraints. The present work concerns the tooling and process factors that influence micro injection moulding. The requirements of this manufacturing process are identified, and a review of the current state of the art in the field, Chapter 2, is used to assess the potential of this technology. To analyse further the manufacturing capabilities of this technology against the requirements, an investigation of the pre-filling, filling and part removal stages of the process cycle is conducted. In particular, in Chapter 3 the pre-filling capabilities of multi cavity micro tools with the use of a runner system is explored. The filling performance of spiral-like micro cavities was studied as a function of runner size in combination with selected process factors. Then, in Chapter 4 the filling of micro mould cavities with controlled tool surface finishes is investigated. Factors affecting the flow behaviour are discussed and a special attention is paid to the interaction between the melt flow and the tool surface roughness. Using the same part design as that of the tool surface finish investigation, in Chapter 5 a Finite Element Analysis (FEA) is used to verify the effects of process parameters, particularly the factors affecting shear rate, pressure and temperature. The results of this investigation were then compared with those reported in the experimental study. Finally, in Chapter 6 the application of micro mould surface treatments is analysed. The effects of different surface treatments on the de-moulding of parts with micro features are investigated to identify the best processing conditions in regards to de-moulding behaviour. To validate the process effects for these three process stages micro injection moulding experimental set-ups were specially designed and implemented. These experiments apply various part designs, tool-making techniques, process factors, part inspection and condition monitoring techniques, and FEA. To further understand the importance of process characteristics at the micro scale, an in depth analysis of the experimental results for each of the selected investigations was carried out. Finally, in Chapter 7 the results from each of the investigations are summarised, and the main research findings identified, in particular the influence of runner size on the process performance, tool surface finish effects on the filling process, the accuracy and sensitivity of the proposed FEA model, and the effects of tool surface treatment on part de-moulding

    Proceedings of the Seventh Congress of the European Society for Research in Mathematics Education

    Get PDF
    International audienceThis volume contains the Proceedings of the Seventh Congress of the European Society for Research in Mathematics Education (ERME), which took place 9-13 February 2011, at RzeszĂąw in Poland

    Elements of Ion Linear Accelerators, Calm in The Resonances, Other_Tales

    Full text link
    The main part of this book, Elements of Linear Accelerators, outlines in Part 1 a framework for non-relativistic linear accelerator focusing and accelerating channel design, simulation, optimization and analysis where space charge is an important factor. Part 1 is the most important part of the book; grasping the framework is essential to fully understand and appreciate the elements within it, and the myriad application details of the following Parts. The treatment concentrates on all linacs, large or small, intended for high-intensity, very low beam loss, factory-type application. The Radio-Frequency-Quadrupole (RFQ) is especially developed as a representative and the most complicated linac form (from dc to bunched and accelerated beam), extending to practical design of long, high energy linacs, including space charge resonances and beam halo formation, and some challenges for future work. Also a practical method is presented for designing Alternating-Phase- Focused (APF) linacs with long sequences and high energy gain. Full open-source software is available. The following part, Calm in the Resonances and Other Tales, contains eyewitness accounts of nearly 60 years of participation in accelerator technology. (September 2023) The LINACS codes are released at no cost and, as always,with fully open-source coding. (p.2 & Ch 19.10)Comment: 652 pages. Some hundreds of figures - all images, there is no data in the figures. (September 2023) The LINACS codes are released at no cost and, as always,with fully open-source coding. (p.2 & Ch 19.10

    PROCEEDINGS 5th PLATE Conference

    Get PDF
    The 5th international PLATE conference (Product Lifetimes and the Environment) addressed product lifetimes in the context of sustainability. The PLATE conference, which has been running since 2015, has successfully been able to establish a solid network of researchers around its core theme. The topic has come to the forefront of current (political, scientific & societal) debates due to its interconnectedness with a number of recent prominent movements, such as the circular economy, eco-design and collaborative consumption. For the 2023 edition of the conference, we encouraged researchers to propose how to extend, widen or critically re-construct thematic sessions for the PLATE conference, and the paper call was constructed based on these proposals. In this 5th PLATE conference, we had 171 paper presentations and 238 participants from 14 different countries. Beside of paper sessions we organized workshops and REPAIR exhibitions

    Proceedings of the 21st International Congress of Aesthetics, Possible Worlds of Contemporary Aesthetics Aesthetics Between History, Geography and Media

    Get PDF
    The Faculty of Architecture, University of Belgrade and the Society for Aesthetics of Architecture and Visual Arts of Serbia (DEAVUS) are proud to be able to organize the 21st ICA Congress on “Possible Worlds of Contemporary Aesthetics: Aesthetics Between History, Geography and Media”. We are proud to announce that we received over 500 submissions from 56 countries, which makes this Congress the greatest gathering of aestheticians in this region in the last 40 years. The ICA 2019 Belgrade aims to map out contemporary aesthetics practices in a vivid dialogue of aestheticians, philosophers, art theorists, architecture theorists, culture theorists, media theorists, artists, media entrepreneurs, architects, cultural activists and researchers in the fields of humanities and social sciences. More precisely, the goal is to map the possible worlds of contemporary aesthetics in Europe, Asia, North and South America, Africa and Australia. The idea is to show, interpret and map the unity and diverseness in aesthetic thought, expression, research, and philosophies on our shared planet. Our goal is to promote a dialogue concerning aesthetics in those parts of the world that have not been involved with the work of the International Association for Aesthetics to this day. Global dialogue, understanding and cooperation are what we aim to achieve. That said, the 21st ICA is the first Congress to highlight the aesthetic issues of marginalised regions that have not been fully involved in the work of the IAA. This will be accomplished, among others, via thematic round tables discussing contemporary aesthetics in East Africa and South America. Today, aesthetics is recognized as an important philosophical, theoretical and even scientific discipline that aims at interpreting the complexity of phenomena in our contemporary world. People rather talk about possible worlds or possible aesthetic regimes rather than a unique and consistent philosophical, scientific or theoretical discipline
    corecore