Browsing by Author "Jolly, Mark R."
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Item Open Access Assessment of casting filling by modeling surface entrainment events using CFD(The Minerals, Metals and Materials Society, 2010-05-31) Reilly, C.; Jolly, Mark R.; Green, N. R.; Gebelin, J. C.The reliability of cast components is dependent on the quality of the casting process. During this highly transient filling phase the prevention of free surface turbulence and consequential oxide entrainment is critical to ensure the mechanical integrity of the component. Past research has highlighted a number of events that lead to entrainment of surface oxides. Using FLOW-3D, flow structures that result in surface entrainment events have been simulated and an algorithm developed that allows entrainment and defect motion to be tracked. This enables prediction of the quantity and motion of oxide film generated from each event. The algorithm was tested experimentally and compared to experimental data from previously published work. A quantitative criterion is proposed to assess the damage of each type of event. Complete running systems have also been studied to understand how they could be assessed for quality of filling based on the flows within them.Item Open Access Automatically weighted high-resolution mapping of multi-criteria decision analysis for sustainable manufacturing systems(Elsevier, 2020-02-01) Pagone, Emanuele; Salonitis, Konstantinos; Jolly, Mark R.A common feature of Multi-Criteria Decision Analysis (MCDA) to evaluate sustainable manufacturing is the participation (to various extents) of Decision Makers (DMs) or experts (e.g. to define the importance, or “weight”, of each criterion). This is an undesirable requirement that can be time consuming and complex, but it can also lead to disagreement between multiple DMs. Another drawback of typical MCDA methods is the limited scope of weight sensitivity analyses that are usually performed for one criterion at the time or on an arbitrary basis, struggling to show the “big picture” of the decision making space that can be complex in many real-world cases. This work removes all the mentioned shortcomings implementing automatic weighting through an ordinal combinatorial ranking of criteria objectively set by four pre-defined weight distributions. Such solution provides the DM not only with a fast, rational and systematic method, but also with a broader and more accurate insight into the decision making space considered. Additionally, the entropy of information in the criteria can be used to adjust the weights and emphasise the differences between potentially close alternativeItem Open Access The capability enhancement of aluminium casting process by application of the novel CRIMSON method(Wiley, 2011-04-19) Dai, Xiaojun; Jolly, Mark R.; Zeng, BinxuThe conventional foundry not only frequently uses batch melting, where the aluminium alloys are melted and held in a furnace for long time, sometimes as long as a complete shift, but also uses the gravity sand casting process where the molten aluminium alloys are transferred using a ladle from furnace to pour station and are poured into a mould. During the filling of the mould, the turbulent nature of the liquid metal gives rise to massive entrainment of the surface oxide films which are the subsequently trapped into the liquid and act as micro cracks. Also the long exposure time of the liquid surface to the surrounding environment during melting, transferring and filling will increase the level of hydrogen absorption from the atmosphere. The abovementioned factors are often the main reasons for casting defect generation. In this paper the novel CRIMSON aluminium casting method is introduced which has a number of advantages. Instead of gravity filling method, it uses the single shot upcasting method to realize the rapid melting and rapid counter-gravity-filling mould operations which reduce the contact time between the melt and environment thus reducing the possibility of defect generation. Another advantage is the drastic reduction of energy consumption due to shortened melting and filling time. A simulation software, FLOW-3D, is used to compare this new method with the conventional gravity casting process. A tensile bar case is used as a sample to simulate the filling process.Item Open Access Caught in the act: The structural pathway of liquid metals to vitrification monitored in situ by synchrotron X-ray diffraction.(Cranfield University, 2021-09) Stiehler, Martin E.; Georgarakis, Konstantinos; Jolly, Mark R.When a metallic melt is undercooled fast enough below its liquidus temperature, crystallisation can be avoided and a metallic glass, i.e. a metallic solid with amorphous structure, be formed. This kind of solidification is called vitrification. The prerequisites for this phenomenon are still not clear. An extensive review of the available relevant literature was carried out. To reveal the structural changes taking place at the atomic scale during undercooling and vitrification, data obtained by ultrafast synchrotron X-ray diffraction during aerodynamic-levitation experiments of different metallic-glass forming liquids was analysed. The complete pathway from temperatures well above the liquidus temperature during undercooling and vitrification down to temperatures well below the glass-transition temperature Tg was studied. During undercooling, a non-linear evolution of structural metrics in real as well as in reciprocal space takes place. Especially the height of the first maximum in the structure factor can be described by a structural analogue to the Curie-Weiss law. This behaviour was also found in published data re-analysed here. Indications of universal behaviour among the investigated alloys below a certain temperature as well as for a liquid-liquid crossover in Ti₄₀Cu₃₄Pd₁₄Zr₁₀Sn₂ were found. Small differences in the temperature dependence of the structural behaviour among the different alloys are possibly related to their different glass-forming abilities. To facilitate the analysis of the real-space structure the novel concept of the anti-shell was introduced. Temperature affects different length scales differently. Below Tg the structural behaviour is dominated by the Debye-Waller factor as well as by normal thermal-expansion behaviour. Above Tg an apparent negative thermal expansion of the first nearest-neighbour distance can be attributed to the influence of the structure-forming processes. In addition to short- and medium-range order, a third structural range for distances beyond the third nearest-neighbour is proposed. A disordering of the atomic structure of metallic glasses by the introduction of further alloying elements, facilitated by emergent effects among the components, could be demonstrated. The importance of the influence of global electronic interactions on structure formation was shown as well as their limitation to distances beyond the third nearest-neighbour.Item Open Access The challenges for energy efficient casting processes(Elsevier, 2016-02-19) Salonitis, Konstantinos; Zeng, Binxu; Mehrabi, Hamid Ahmad; Jolly, Mark R.Casting is one of the oldest, most challenging and energy intensive manufacturing processes. A typical modern casting process contains six different stages, which are classified as melting, alloying, moulding, pouring, solidification and finishing respectively. At each stage, high level and precision of process control is required. The energy efficiency of casting process can be improved by using novel alterations, such as the Constrained Rapid Induction Melting Single Shot Up-casting process. Within the present study the energy consumption of casting processes is analyzed and areas were great savings can be achieved are discussed. Lean thinking is used to identify waste and to analyse the energy saving potential for casting industry.Item Open Access Comparison of the environmental impact of the CRIMSON process with normal sand casting process(2013-09-02T00:00:00Z) Zeng, Binxu; Salonitis, Konstantinos; Jolly, Mark R.; Shehab, Essam; Ball, Peter D.; Tjahjono, BennyThe CRIMSON process is an alternative process to conventional casting that can be used for small to medium batch sizes. The aim of this process are to improve the casting quality and reduce the energy consumption within light-metal casting industry. Nowadays, the energy efficiency becomes more and more important. This is not only about the cost of the production, but also about the environmental effect. In this paper, the CRIMSON process will be compared with the conventional sand casting process. The Life cycle assessment (LCA) method will be used to assess the environmental impact of both casting processes.Item Open Access Comparison of the environmental impact of the crimson process with normal sand casting process(Cranfield University Press, 2013-09-19) Zeng, Binxu; Salonitis, Konstantinos; Jolly, Mark R.The CRIMSON process is an alternative process to conventional casting that can be used for small to medium batch sizes. The aim of this process are to improve the casting quality and reduce the energy consumption within light-metal casting industry. Nowadays, the energy efficiency becomes more and more important. This is not only about the cost of the production, but also about the environmental effect. In this paper, the CRIMSON process will be compared with the conventional sand casting process. The Life cycle assessment (LCA) method will be used to assess the environmental impact of both casting processes.Item Open Access A computational framework towards energy efficient casting processes(Springer, 2018-12-01) Papanikolaou, Michail; Pagone, Emanuele; Salonitis, Konstantinos; Jolly, Mark R.; Makatsoris, MakatsorisCasting is one of the most widely used, challenging and energy intensive manufacturing processes. Due to the complex engineering problems associated with casting, foundry engineers are mainly concerned with the quality of the final casting component. Consequently, energy efficiency is often disregarded and huge amounts of energy are wasted in favor of high quality casting parts. In this paper, a novel computational framework for the constrained minimization of the pouring temperature is presented and applied on the Constrained Rapid Induction Melting Single Shot Up-Casting (CRIMSON) process. Minimizing the value of the pouring temperature can lead to significant energy savings during the melting and holding processes as well as to higher yield rate due to the resulting reduction of the solidification time. Moreover, a multi-objective optimization component has been integrated into our scheme to assist decision makers with estimating the trade-off between process parameters.Item Open Access Continuous and sustainable cellulose filaments from ionic liquid dissolved paper sludge nanofibres(Elsevier, 2020-10-03) Adu, Cynthia; Zhu, Chenchen; Jolly, Mark R.; Richardson, Robert M.; Eichhorn, Stephen J.The textile industry is resource intensive, which has a significant impact on global emissions and waste pollution. To meet the demand of textiles over a third of fibres used in manufacturing are sourced from fossil fuels. As the global demand for textiles continues to grow, manufacturers have having to seek innovative approaches to providing sustainable regenerative cellulose fibres. However, the latest climate change pressures on the textile industry has uncovered grave environmental issues associated with traditional regenerative cellulose production such as the viscose manufacturing process. The viscose process the required intensive use of hazardous chemicals which leads to water pollution and ecotoxicity. In addition, if forestry products are unsustainably sourced for the viscose production this can lead to resource scarcity and deforestation. To provide a holistic solution for mitigating these challenges this study uses the by-products of paper manufacturing dissolved in an ionic liquid to produce regenerated cellulose filaments. Paper mill sludge (PMS) is a cellulosic by-product typically used on animal bedding and land spreading. The material has been dissolved in an ionic liquid - 1-ethyl-3-methylimidazolium diethyl phosphate - with the aid of a co-solvent dimethyl sulfoxide (DMSO) - and spun into continuous filaments for textile production. The mechanical properties of paper sludge filaments are found to be competitive with commercial viscose, which is promising for their drop-in replacement. It is also demonstrated that by increasing the concentration of the PMS from 9% to 12.4%, an improvement of the filament properties can be achieved; an increase in modulus from ~19 GPa to ~ 26 GPa and ~ 223 MPa to ~ 282 MPa. These values are shown to be competitive with other commercial, less sustainable, regenerated cellulose fibresItem Open Access Design optimisation of the feeding system of a novel counter-gravity casting process(MDPI, 2018-10-11) Papanikolaou, Michail; Pagone, Emanuele; Georgarakis, Konstantinos; Rogers, Keith; Jolly, Mark R.; Salonitis, KonstantinosThe appropriate design of feeders in a rigging system is critical for ensuring efficient compensation for solidification shrinkage, thus eliminating (shrinkage-related) porosity and contributing to the production of superior quality castings. In this study, a multi-objective optimisation framework combined with Computational Fluid Dynamics (CFD) simulations has been introduced to investigate the effect of the feeders’ geometry on shrinkage porosity aiming to optimise casting quality and yield for a novel counter-gravity casting process (CRIMSON). The weighted sum technique was employed to convert this multi-objective optimisation problem to a single objective one. Moreover, an evolutionary multi-objective optimisation algorithm (NSGA-II) has been applied to estimate the trade-off between the objective functions and support decision makers on selecting the optimum solution based on the desired properties of the final casting product and the process characteristics. This study is one of the first attempts to combine CFD simulations with multi-objective optimisation techniques in counter-gravity casting. The obtained results indicate the benefits of applying multi-objective optimisation techniques to casting processesItem Open Access Designing a circular business model from industrial by-products: A case study on paper mill sludge(Cranfield University, 2019-10) Adu, Cynthia Ediabai; Jolly, Mark R.; Eichhorn, StephenThe circular economy (CE) emphasises the optimisation of resource yields by keeping products, components and materials at their highest utility and value. This recently popularised concept has created awareness within businesses, government and policymakers. However, there is a discourse that the concept lacks scientific rigour and has primarily been led by practitioners such as policy makers, social scientists and business consultants. Resources in the CE concept are referred to as biological nutrients and technical nutrients. Based on the CE resource recovery model, biological nutrients such as organic waste/by-products are expected to return to the system. However, the current waste management sector is not equipped with how to innovate and/or create value from resources termed as waste/by-products. Whilst CE is a commendable strategy with insightful case studies, the philosophy currently lacks robust design guidance that can provide businesses with the tools and tactics required to meet the agenda. Therefore, this EngD research applies design thinking innovation methodology to an existing business faced with the challenge of adopting a circular business model for resource recovery. The EngD research is based on Ecoganix, an organic waste treatment company. Ecoganix manages Paper Mill Sludge (PMS), a by-product derived from the waste-water treatment of paper mills. In the UK, a million tonnes of PMS is currently produced annually. The management of PMS is an environmental challenge and the second highest cost for the sector after energy consumption. The PMS is collected by Ecoganix from 7 paper mills in the UK for use as soil improvement on farm land . The current management system of PMS is unsustainable and short-term. Moreover, the market is highly competitive due to increasing recycling rates and competitive pricing. Nonetheless, this material PMS is rich in organic cellulose fibres and inorganic minerals. Thus, a design thinking methodology is used to create new value streams of materials from this byproduct...[cont.]Item Open Access Developing fiber and mineral based composite materials from paper manufacturing by-products(Springer, 2017-04-27) Adu, Cynthia; Jolly, Mark R.Developing valuable materials from the by-products of paper industry can help to address some environmental and economic issues associated with traditional synthetic composites. Particularly, the management of paper mill sludge (PMS) waste remains an economic and environmental challenge for the pulp and paper industry. 11 million tons of PMS is generated annually in Europe from the wastewater treatment (WWT) process of paper mills. PMS is mostly used in low value applications. However, PMS contains fibers and minerals with physio-chemical properties that exhibit a high potential to substitute some conventional materials in other industries. The research presented in this paper aims to explore new directions for further investigation on PMS material applications by reviewing the literature on PMS materials and subsequently characterizing sludge from 6 different mills. The study shows the technical feasibility, opportunities and technological readiness of fiber and mineral based composites obtained from PMS, such as; cementitious products, polymer reinforcement and fiberboards.Item Open Access The development of a tool to promote sustainability in casting processes(Elsevier, 2016-11-02) Pagone, Emanuele; Jolly, Mark R.; Salonitis, KonstantinosThe drive of the manufacturing industry towards productivity, quality and profitability has been supported in the last century by the availability of relatively cheap and abundant energy sources with limited focus on the minimisation of energy and material waste. However, in the last decades, more and more stringent regulations aimed at reducing pollution and consumption of resources have been introduced worldwide and in particular in Europe. Consequently, a highly mature and competitive industry like foundry is expecting challenges that an endeavour towards sustainability can turn into significant opportunities for the future. A tool to undertake a systematic analysis of energy and material flows in the casting process is being developed. An overview of the computer program architecture is presented and its output has been validated against real-world data collected from foundries.Item Open Access Effect of batch initial velocity on the glass furnace efficiency(WIley, 2014-01-10) Soleimanian, Nasim; Jolly, Mark R.; Dearn, Karl; Brinkman, Oliver; Brinkman, WilliamGlass manufacturing is a heat intensive process. There is a direct coloration between the batch distribution techniques and the furnace energy consumption, productivity, and quality of the glass manufactured. All four major segments (float, container, fibre, and specialty glasses) would benefit from using an optimised batch distribution technique where possible. Oscillating batch chargers (OBC) have been in use since the early 70s, despite their superior batch shape, coverage, and in turn positive effects on the energy consumption (Soleimanian, TMS 2013) and productivity of the furnace they are almost exclusively used in container glass manufacturing. The OBC’s main difference compared with other charging methods is its ability to directly influence the batch initial velocity. This paper reports on results achieved in two CFD models (in Flow 3D and GFM) used to study effect of the machine on the overall energy consumption in the doghouse and the melt space.Item Open Access The effect of Ni or Co additions on the structure of Zr60Cu30Al10 bulk metallic glass revealed by high-energy synchrotron radiation(Elsevier, 2022-04-13) Stiehler, Martin E.; Panagiotopoulos, Nikolaos T.; Keeble, Dean S.; Ivanov, Yurii P.; Menelaou, Melita; Jolly, Mark R.; Greer, A.Lindsay; Georgarakis, KonstantinosThe effect of substituting Cu by elemental additions of Ni or Co on the atomic structure of the Zr60Cu30Al10 ternary bulk metallic glass (BMG) is studied using high-energy synchrotron radiation X-ray diffraction. Analyses of the structural features in reciprocal and real space using the structure factors S(Q) and pair-distribution functions (PDF) point to an increase in the structural disorder for the Ni- or Co-bearing quaternary alloys. This is consistent with the “confusion principle” since upon alloying the initially nearly identical atomic sizes of Cu, Ni and Co diversify due to local electronic interactions. In real space, the disordering is manifested by a reduced deviation from the average particle density visible in the nearest-neighbour (NN) atomic shell structure over the complete short- and medium-range order region. Despite their similar atomic size, enthalpies of mixing with the main alloy elements and apparent disordering of the structure, the additions of Ni or Co have different effects on thermal stability of the ternary “mother” alloy.Item Open Access Energy and material efficiency metrics in foundries(Elsevier, 2018-03-07) Pagone, Emanuele; Salonitis, Konstantinos; Jolly, Mark R.Most of the current foundry processes are based on well-developed and established practices typical of mature technologies. Contemporary economic, environmental and societal developments have concurrently changed at an unprecedented rate the context where traditional metal casting methodologies have not really developed much over time. Consequently, significant challenges and opportunities arise. This work will present the founding metrics of a novel approach to metal casting with the development of a new philosophy (called “Small is Beautiful”) aimed at tackling the current pressures on the industry with a focus on energy and materials’ efficiencies and flexible production. Traditional and well-established parameters are presented and compared to new metrics defined from first principles and thermodynamic properties. All metrics are validated using industrial and scientific literature data of five sand casting plants melting different ferrous and non-ferrous alloys.Item Open Access Energy efficiency improvement by implementation of the novel CRIMSON aluminium casting process(2014-02-06) Jolly, Mark R.; Dai, Xiaojun J.; Neelameggham, N. R.; Belt, C. K.; Jolly, Mark R.; Reddy, R. G.; Yurko, J. A.Foundry engineers in the traditional foundry usually regard the quality of casting component as the most important issue and leave the energy saving or energy efficiency as the subsidiary one. This frequently causes disproportionate energy consumption as a result of the inefficient casting processes used and increases the production costs. This paper presents the novel CRIMSON aluminium casting process and compares its facility and melting process with traditional melt furnaces and aluminium alloy melting process. A real example is investigated to demonstrate quantitatively how the traditional foundry wastes energy and what the improvement of energy efficiency can be achieved using the new CRIMSON method. The results of this investigation will help the foundry engineer recognize the importance of energy saving and demonstrate how to use this new technology to reduce production costs and carbon footprint without decreasing the quality of the cast component.Item Open Access Energy efficiency status-quo at UK foundries: the “small-is-beautiful” project(Springer, 2017-02-12) Jolly, Mark R.; Salonitis, Konstantinos; Charnley, Fiona; Ball, Peter D.; Ahmad Mehrabi, Hamid; Pagone, EmanueleItem Open Access Energy resilient foundries: the “Small is beautiful” projects(Springer, 2022-02-05) Jolly, Mark R.; Salonitis, Konstantinos; Pagone, Emanuele; Papanikolaou, Michail; Saxena, PrateekApplying the concept of “small is beautiful” into a conservative relatively low technology manufacturing sector where the “economies of scale” argument has been used to build ever more so-called efficient process lines is a major challenge. The energy efficiency of the casting process has only been investigated in a limited fashion. The two “Small is Beautiful” projects aimed to introduce a new concept into foundries with regards to the use of their resources. The new philosophy, “small is beautiful”, starts by encouraging the use of high-quality feedstock, only melting what is required and only when it is required. Recycling of internal scrap is not necessarily acceptable but an aim for higher yields is. Applying counter gravity casting methods to improve yield and give enhanced quality is encouraged as is the recovery of low-grade heat from solidification. The present paper discusses the research undertaken and the key findings from the two projects.Item Open Access Energy-efficient casting processes(Springer, 2018-12-13) Pagone, Emanuele; Salonitis, Konstantinos; Jolly, Mark R.Metal casting is one of the most energy-intensive manufacturing processes that have developed along the evolution of mankind. Although nowadays its scientific and technological aspects are well established, in the context of future resource scarcity and environmental pollution pressures, new studies appear necessary to describe the “foundry of the future” where energy and material efficiency are of great importance to guarantee competitiveness alongside environmental protection. In this chapter, both managerial and technical good practices aimed at implementing energy-efficient casting processes are presented alongside a few examples. The “Small is Beautiful” philosophy is presented as a systematic approach towards energy resilient manufacturing and, potentially, sustainability in the long term. Thus, this chapter aims at providing an overview of the different aspects comprising the state of the art in the industry and examples of research themes in academia about energy-efficient casting processes.
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