Viability and performance of demountable composite connectors

AbstractMaterial production, and associated carbon emissions, could be reduced by reusing products instead of landfilling or recycling them. Steel beams are well suited to reuse, but are difficult to reuse when connected compositely to concrete slabs using welded studs. A demountable connection would allow composite performance but also permit reuse of both components at end-of-life. Three composite beams, of 2m, 10m and 5m length, are constructed using M20 bolts as demountable shear connectors. The beams are tested in three-, six- and four-point bending, respectively. The former two are loaded to service, unloaded, demounted and reassembled; all three are tested to failure. The results show that all three have higher strengths than predicted using Eurocode 4. The longer specimens have performance similar to previously published comparable welded-connector composite beam results. This suggests that demountable composite beams can be safely used and practically reused, thus reducing carbon emissions

A Structured Search for Novel Manufacturing Processes Leading to a Periodic Table of Ring Rolling Machines

Manufacturing processes based on cutting have been extensively automated over the past [30][31][32][33][34][35][36][37][38][39][40

Designing climate change mitigation plans that add up.

Mitigation plans to combat climate change depend on the combined implementation of many abatement options, but the options interact. Published anthropogenic emissions inventories are disaggregated by gas, sector, country, or final energy form. This allows the assessment of novel energy supply options, but is insufficient for understanding how options for efficiency and demand reduction interact. A consistent framework for understanding the drivers of emissions is therefore developed, with a set of seven complete inventories reflecting all technical options for mitigation connected through lossless allocation matrices. The required data set is compiled and calculated from a wide range of industry, government, and academic reports. The framework is used to create a global Sankey diagram to relate human demand for services to anthropogenic emissions. The application of this framework is demonstrated through a prediction of per-capita emissions based on service demand in different countries, and through an example showing how the "technical potentials" of a set of separate mitigation options should be combined

Materials & Manufacturing: Business growth in a transformative journey to zero emissions

Facing the reality that new energy-sector technologies won’t solve climate change fast enough reveals rich opportunities for innovation and growth in UK materials and manufacturing sectors. UK law commits us to zero emissions by 2050 with most of the reduction occurring by 2035. But we’re not on track to deliver. That’s because corporate and political strategy today is counting on new technologies, like carbon capture and storage, biofuels, hydrogen and negative emissions technologies to meet the challenge, while business elsewhere continues largely as usual. It isn’t going to happen in time. The new technologies are mainly still on drawing boards, and it takes time to deploy them at scale. Instead, delivering zero emissions in reality by 2050 requires a different economy. It’s one that can deliver high quality lifestyles, but it’s an economy that will be powered only by emissions free electricity. We won’t have as much electricity as we’d otherwise like, so we’ll reduce our use of two-tonne cars and badly insulated houses, for example. For some time we’ll have to restrain our use of goods, like ruminants and cement, that can’t be electrified. But this new economy can deliver great lifestyles and great businesses. In manufacturing, we won’t be able to access the same volumes of material as in the emitting past, but we have the opportunity for huge growth in the UK. The closure of high-emitting international freight will open up new demand for domestic production. The need to close the high-emitting material suppliers of the past creates new opportunities for electric materials production. The business of matching material supply to consumer demand for goods will transform and grow

Scrap, carbon and cost savings from the adoption of flexible nested blanking

Abstract: Steel accounts for 6% of anthropogenic CO2 emissions, most of which arises during steelmaking rather than downstream manufacturing. While improving efficiency in steelmaking has received a great deal of attention, improving material yield downstream can have a substantial impact and has received comparatively less attention. In this paper, we explore the conditions required for manufacturers to switch to a more materially efficient process, reducing demand for steel and thus reducing emissions without reducing the supply of goods to consumers. Furthermore, we present an alternative processing route where parts can be cut in flexible arrangements to take advantage of optimal nesting across multiple part geometries. For the first time, we determine the potential savings that flexible nested blanking of parts could achieve by calculating the potential for grouping orders with tolerably similar thickness, strengths, ductility and corrosion-resistance. We found that 1080 kt of CO2 and 710 kt of steel worth €430M could be saved each year if this scheme was adopted across all European flat steelmills serving the automotive sector

Mapping the global flow of aluminum: from liquid aluminum to end-use goods.

Demand for aluminum in final products has increased 30-fold since 1950 to 45 million tonnes per year, with forecasts predicting this exceptional growth to continue so that demand will reach 2-3 times today's levels by 2050. Aluminum production uses 3.5% of global electricity and causes 1% of global CO2 emissions, while meeting a 50% cut in emissions by 2050 against growing demand would require at least a 75% reduction in CO2 emissions per tonne of aluminum produced--a challenging prospect. In this paper we trace the global flows of aluminum from liquid metal to final products, revealing for the first time a complete map of the aluminum system and providing a basis for future study of the emissions abatement potential of material efficiency. The resulting Sankey diagram also draws attention to two key issues. First, around half of all liquid aluminum (~39 Mt) produced each year never reaches a final product, and a detailed discussion of these high yield losses shows significant opportunities for improvement. Second, aluminum recycling, which avoids the high energy costs and emissions of electrolysis, requires signification "dilution" (~ 8 Mt) and "cascade" (~ 6 Mt) flows of higher aluminum grades to make up for the shortfall in scrap supply and to obtain the desired alloy mix, increasing the energy required for recycling

The influence of part asymmetry on the achievable forming height in multi-pass spinning

Metal spinning is an incremental forming technique commonly employed in the production of hollow axisymmetric components. In recent years, asymmetric spinning processes have been developed to expand the range of component geometries achievable by the technique. However, most of these processes have employed a solid mandrel to set the target shape and provide internal support to the workpiece, thus requiring new tooling to be manufactured for every new part. Moreover, no studies have been performed on the link between the geometry of the target part and the achievable forming height. In this paper, the range of curvature in the target part's planform is used to quantify its degree of asymmetry, and the influence of this parameter on the formability of spun parts is investigated in a series of experimental trials. The hypothesis that the range of planform curvature predicts the likelihood of workpiece failure is tested. Methods to design the multi-pass toolpaths and the blanks required to spin both axisymmetric and asymmetric components without a mandrel are developed. The results show that increasing the degree of asymmetry of the target part only weakly influences the achievable forming height. This finding points to the potential of the technique to produce multiple geometries flexibly and to reduce the costs of prototyping and testing new sheet metal parts considerably.IMR is supported by a Doctoral Training Partnership (DTP) studentship provided by the UK's Engineering and Physical Sciences Research Council (EPSRC). CJC and JMA are supported by EPSRC grant EP/K018108/1. EGL is supported by EPSRC grant EP/S515760/1. EGL also acknowledges support from an Innovate UK project (FELDSPAR) and earlier funding from Nissan Motor Co., Ltd

Material Flow Analysis with Multiple Material Characteristics to Assess the Potential for Flat Steel Prompt Scrap Prevention and Diversion without Remelting.

Thirty-two percent of the liquid metal used to make flat steel products in Europe does not end up in a final product. Sixty percent of this material is instead scrapped during manufacturing and the remainder during fabrication of finished steel products. Although this scrap is collected and recycled, remelting this scrap requires approximately 2 MWh/t, but some of this material could instead be diverted for use in other applications without remelting. However, this diversion depends not just on the mass of scrapped steel but also on its material characteristics. To enhance our understanding of the potential for such scrap diversion, this paper presents a novel material flow analysis of flat steel produced in Europe in 2013. This analysis considers the flow of steel characterized not only by mass but, for the first time, also by grade, thickness, and coating. The results show that thin-gauge galvanized drawing steel is the most commonly demanded steel grade across the industry, and most scrap of this grade is generated by the automotive industry. There are thus potential opportunities for preventing and diverting scrap of this grade. We discuss the role of the geometric compatibility of parts and propose tessellating blanks for various car manufacturers in the same coil of steel to increase the utilization rates of steel.EPSR

Material Stock Demographics: Cars in Great Britain.

Recent literature on material flow analysis has been focused on quantitative characterization of past material flows. Fewer analyses exist on past and prospective quantification of stocks of materials in-use. Some of these analyses explore the composition of products' stocks, but a focus on the characterization of material stocks and its relation with service delivery is often neglected. We propose the use of the methods of human demography to characterize material stocks, defined herein as stock demographics, exploring the insights that this approach could provide for the sustainable management of materials. We exemplify an application of stock demographics by characterizing the composition and service delivery of iron, steel, and aluminum stocks of cars in Great Britain, 2002-2012. The results show that in this period the stock has become heavier, it is traveling less, and it is idle for more time. The visualization of material stocks' dynamics demonstrates the pace of product replacement as a function of its usefulness and enables the formulation of policy interventions and the exploration of future trends.This work was supported by EPSRC, grant reference EP/N02351X/1.This is the final version of the article. It first appeared from the American Chemical Society via https://doi.org/10.1021/acs.est.5b0501