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Climate and agriculture have played an interconnected role in the rise and fall of historical civilizations. Our modern food system, based on open-environment production and globalised supply chains, is vulnerable to a litany of abiotic and biotic stressors exacerbated by anthropogenic climate change. Despite this evidence, greenhouse gas emissions continue to rise. Current trajectories suggest global warming of ∼2.0–4.9 °C by 2100, however, a worst-case emissions scenario with rapid combustion of all available fossil fuels could cause a rise of ∼12 °C. Even if emissions decline, unprecedented atmospheric CO 2 -e concentrations risk triggering tipping points in climate system feedbacks that may see global warming exceed 8 °C. Yet, such speculative 'runaway global warming' has received minimal attention compared to mainstream low- to mid-range scenarios. This study builds on The Limits to Growth to provide new insights into the international risk of mass mortality due to food insecurity based on a higher-resolution illustration of World3's 'runaway global warming' scenario (∼8–12 °C+). Our simulation indicates rapid decline in food production and unequal distribution of ∼6 billion deaths due to starvation by 2100. We highlight the importance of including high-resolution simulations of high-range global warming in climate change impact modelling to make well-informed decisions about climate change mitigation, resilience and adaptation. • Establishes that high-range global warming is understudied compared to low- to mid-range scenarios, and our modern globalised food system is uniquely vulnerable to climate change. • Provides new insights into World3's 'runaway global warming' (8–12 °C+ by 2100) scenario using accelerated high-resolution SSP5-RCP85 data. • Develops a computational model to explore international risk of mass mortality due to food insecurity under the artificial 'runaway global warming' scenario. • Asserts the importance of high-resolution simulations of high-range global warming to inform mitigation, vulnerability, resilience and adaptation solutions. • Highlights the unequal distribution of potential human suffering, inequality and emissions, and the need for intervention strategies tailored to local contexts. [ABSTRACT FROM AUTHOR]

Most sheet metal components are made by deep drawing, which requires expensive tooling. Although many new flexible forming processes have been invented, they have largely not had industrial application, so it would be valuable if intelligent means to design new processes existed. This has not previously been attempted, although there has been work to classify both products and processes and to define optimal forming processes. A body of work in garment production examines the optimal flattening of garments, starting from their final form on a human body, to deduce the best cutting pattern from flat fabric. This paper develops a related approach for the first time, “un-forming” sheet metal from its finished geometry to a flat blank without prior specification of a process. An algorithm is developed that allows specification of process constraints and great freedom in implementing un-forming strategies, leading to a prediction of the strain history of the un-forming process. Reversing the direction of this history, allows prediction of the stresses in the workpiece required to form the target part, by use of an appropriate material model. The external forces (boundary conditions) required to maintain equilibrium with this stress state can then be calculated, allowing an iterative refinement of the constraints on un-forming until a physically achievable process has been designed. The approach is validated against a known process, and used to demonstrate how several previously untried forming strategies could lead to specification of new process designs. In future work, the method could be extended to allow an iterative specification of tooling to create the required boundary conditions, and hence to complete automatic process designs. [ABSTRACT FROM AUTHOR]

Metal forming processes operate in conditions of uncertainty due to parameter variation and imperfect understanding. This uncertainty leads to a degradation of product properties from customer specifications, which can be reduced by the use of closed-loop control. A framework of analysis is presented for understanding closed-loop control in metal forming, allowing an assessment of current and future developments in actuators, sensors and models. This leads to a survey of current and emerging applications across a broad spectrum of metal forming processes, and a discussion of likely developments. [ABSTRACT FROM AUTHOR]

Metal forming is not only shaping the form of a product, it is also influencing its mechanical and physical properties over its entire volume. Advanced analysis methods recently enable accurate prediction of these properties and allow for setting these properties deterministically during the forming process. Effective measurement methods ensure the setting of these predicted properties. Several real examples demonstrate the impressive achievements and indicate the necessity of a paradigm change in designing products by including manufacturing-induced effects in the initial dimensioning. This paradigm change will lead to lightweight components and serve environmentally benign designs. [ABSTRACT FROM AUTHOR]

Abstract: Consumer goods contribute to anthropogenic climate change across their product life cycles through carbon emissions arising from raw materials extraction, processing, logistics, retail and storage, through to consumer use and disposal. How can consumer goods manufacturers make stepwise reductions in their product life cycle carbon emissions by engaging with, and influencing their main stakeholders? A semi-structured interview approach was used: to identify strategies and actions, stakeholders in the consumer goods industry (suppliers, manufacturers, retailers and NGOs) were interviewed about carbon emissions reduction projects. Based on this, a summarising presentation was made, which was shared during a second round of interviews to validate and refine the results. The results demonstrate several opportunities that have not yet been exploited by companies. These include editing product choice in stores to remove products with higher carbon footprints, using marketing competences for environmental benefits, and bundling competences to create win–win–win business models. Governments and NGOs have important enabling roles to accelerate industry change. Although this work was initially developed to explore how companies can reduce life cycle carbon emissions of their products, these strategies and actions also give insights on how companies can influence and anticipate stakeholder actions in general. [Copyright &y& Elsevier]

Abstract: Ever increasing demands on functional integration of high strength light weight products leads to the development of a new class of manufacturing processes. The application of bulk forming processes to sheet or plate semi-finished products, sometimes in combination with conventional sheet forming processes creates new products with the requested properties. The paper defines this new class of sheet-bulk metal forming processes, gives an overview of the existing processes belonging to this class, highlights the tooling aspects as well as the resulting product properties and presents a short summary of the relevant work that has been done towards modeling and simulation. [Copyright &y& Elsevier]

Abstract: Pressure on consumer goods manufacturers to develop new products with significantly less environmental impact is growing, through increased consumer awareness of environmental issues and governments setting ambitious emissions reductions targets. A strategic response to this pressure is to prepare a portfolio of innovative product ideas to meet a range of future emissions reductions targets. However, although extensive work exists on ideation (the generation of novel product ideas) and eco-design (design for reduced environmental impact), eco-ideation (generation of ideas that particularly aim to reduce environmental impacts) has had little attention. The challenge of eco-ideation is to release the creativity of a broad range of employees, only few of whom may be familiar with the drivers of environmental impact. This paper proposes a novel tool to facilitate the generation of radical product and process ideas giving step-change reductions in greenhouse gas emissions. The features of products and processes that drive greenhouse gas emissions across the product life cycle were characterized with a set of indicators. A simple visual tool was created to show these indicators on a sliding scale between best and worst imaginable performance. A leading question associated with each slider was designed to stimulate lower impact ideas. The tool was iteratively refined and simplified through structured testing with individuals from across a range of roles and differing knowledge of environmental impacts. The final eco-ideation tool used 14 scales, with leading questions for each scale developed to stimulate idea generation. The tool’s effectiveness was evaluated through use in a series of 15 individual workshops and compared with the outcomes of an equal number of conventional 12-person group-brainstorming sessions. The comparison suggests that using the simple tool generally leads to a wider range of more radical ideas than emerge from group brainstorming. [Copyright &y& Elsevier]

Abstract: Existing tests for assessing the formability of sheet metal samples can create strain ratios in the range from uniaxial to biaxial stretching, −1/2≤ ɛ 2/ɛ 1 ≤1. A novel sample design is proposed, with shaped cut-outs in a rectangular sheet specimen, intended to produce with strain ratios in the range, −1≤ ɛ 2/ɛ 1 ≤1/2 in a small zone, while the sample is uniaxially extended. The strain ratio is controlled by changing the geometry of the cut-outs. The behaviour of the new sample design is examined by finite element modelling showing nearly proportional behaviour in the test zone, with the best results occurring near to pure shear. Two experimental methods are considered for the validation of these predictions: measurement of the distortion of a grid of small circles created on the sample surface by laser-scribing; use of a commercial strain measurement system based on an applied speckle pattern. Both techniques demonstrate that the evolution of experimentally measured strains during the test closely follows that predicted numerically. The novel sample is applied to test the formability of a range of materials known to be difficult to form. The tests on aluminium alloys Al 2024, Al 7075, Al 2198 and commercially pure titanium demonstrate that significantly enhanced deformation prior to failure is possible with loading near to pure shear. The implication of these results is that it may be possible to design novel forming processes capable of creating more dramatic deformation in “difficult to form” materials through the creation of strain paths close to pure shear. [Copyright &y& Elsevier]

Abstract: This review presents a thorough survey of academic work on the analysis and application of the mechanics of spinning. It surveys most literature published in English and the most important publications in German and Japanese languages. The review aims to provide insight into the mechanics of the process and act as a guide for researchers working on both metal spinning and other modern flexible forming processes. The review of existing work has revealed several gaps in current knowledge of spinning mechanics: the evolution of the stress state and the strain history of the workpiece in both conventional and shear spinning is not well understood, mainly due to the very long solution times that would occur in modelling the process throughout its duration with a sufficiently fine mesh to capture detailed behaviour through the workpiece thickness; the evolution of microstructure, residual stress and hence springback, has not been examined—either numerically or by experiment; the failure mechanisms of spinning – fracture and wrinkling – are only partially understood, through analogy with other processes, and as yet models of the process have not made use of contemporary damage mechanics; the design of toolpaths required to make particular parts without failure remains an art, and cannot currently be performed automatically with confidence. Studies on novel process configurations in spinning have shown that great potential for innovation in spinning exists. The process has the potential to be more flexible, to produce a wider range of shapes, and to form more challenging materials. [Copyright &y& Elsevier]

Abstract: The objective of this study was to compare the life-cycle environmental impacts of changed production structures for two consumer goods (high-density polyethylene (HDPE) shopping bags and beds) in Jamaica. A scenario technique was used to construct three alternative production structures for each product; each scenario reflecting an increase in local production in Jamaica which depended on an increased supply of input materials which may be sourced: (1) externally from overseas suppliers, (2) from post-consumer recycling, and (3) locally on the island of Jamaica. These three constructed scenarios were then compared to the existing supply chain or reference scenarios of the products. The results showed that for both case products the recycling scenario was most preferable for localising production, resulting in the lowest environmental impact. This was because the production of raw materials accounted for the largest effect on total environmental impact. As such, the most immediate environmental improvements were realised by lowering the production of virgin materials. [Copyright &y& Elsevier]

Abstract: Companies aiming to be ‘sustainability leaders’ in their sector and governments wanting to support their ambitions need a means to assess the changes required to make a significant difference in the impact of their whole sector. Previous work on scenario analysis/scenario planning demonstrates extensive developments and applications, but as yet few attempts to integrate the ‘triple bottom line’ concerns of sustainability into scenario planning exercises. This paper, therefore, presents a methodology for scenario analysis of large change to an entire sector. The approach includes calculation of a ‘triple bottom line graphic equaliser’ to allow exploration and evaluation of the trade-offs between economic, environmental and social impacts. The methodology is applied to the UK''s clothing and textiles sector, and results from the study of the sector are summarised. In reflecting on the specific study, some suggestions are made about future application of a similar methodology, including a template of candidate solutions that may lead to significant reduction in impacts. [Copyright &y& Elsevier]

Abstract: 1–2% of global carbon emissions arise in paper production, but the EU plans a 60% cut by 2050. Known process improvements give a 30% cut, but demand may double by 2050: can paper be re-used without recycling by print removal? Three techniques have been developed: abrasion operating in an adhesive wear regime; longer wavelength lasers can ablate toner-print; a solvent can effectively dissolve toner. Energy analysis shows that print removal requires around 10% of the energy required for a new sheet and if this method supplies 80% of future demand, the 2050 carbon target could be achieved. [Copyright &y& Elsevier]

Abstract: Incremental bulk forming is the oldest known technique in metal working. Many developments in this field have dramatically changed our society. Today incremental bulk forming processes are applied to quality products in small and large series production. Numerous advances have been realized. The motivation for using these processes is presented here. After a general definition of incremental processes and a classification of incremental bulk forming in particular, some innovative product and process examples are given that show the potential. Finally recent progress and challenges are illustrated in detail. This includes the development of new machinery for incremental bulk forming, advanced methods for process planning, occurrence of failure modes and the properties of finished products. [Copyright &y& Elsevier]

Abstract: A novel class of ‘paddle forming’ processes for forming pronounced features within sheet metal components is presented. The processes are incremental in nature and are characterised by having contact between the tool and the workpiece along a short line segment. The processes lead to high through-thickness shear strains, which have been shown to increase the possible deformation before ductile instability occurs. Paddle forming tools, which are cheap and simple to manufacture, can be applied to the faces or edges of sheets, tubes and disks. Four example processes are demonstrated, each showing high deformation and pronounced through-thickness shear strain. [Copyright &y& Elsevier]

Abstract: In the past two decades there has been a significant growth of interest in flexible forming processes in Japan, but many new developments are little known elsewhere, particularly when the processes have been reported only within the Japanese literature. This paper presents a thorough survey of recent and current work on flexible forming processes in Japan. The survey was achieved through a series of visits to Japanese laboratories, followed by a literature search, and circulation of a draft of the paper to the key groups active in this area for review and feedback. The processes are described and illustrated, and where possible, brief descriptions of the process capability and limits are given. A classification scheme is developed to organise the flexible processes into a single table and illustrate the possibilities for future innovations in this area. [Copyright &y& Elsevier]