Evaluation Of Vehicle Lightweighting To Reduce Greenhouse Gas Emissions With Focus On Magnesium Substitution

Purpose Vehicle weight reduction represents a viable means of meeting tougher regulatory requirements designed to reduce fuel consumption and control greenhouse gas emissions. This paper aims to present an empirical and comparative analysis of lightweight magnesium materials used to replace conventional steel in passenger vehicles with internal combustion engines. The very low density of magnesium makes it a viable material for lightweighting given that it is lighter than aluminium by one-third and steel by three-fourth. Design/methodology/approach A structural evaluation case study of the “open access” Wikispeed car was undertaken. This included an assessment of material design characteristics such as bending stiffness, torsional stiffness and crashworthiness to evaluate whether magnesium provides a better alternative to the current usage of aluminium in the automotive industry. Findings The Wikispeed car had an issue with the rocker beam width/thickness (b/t) ratio, indicating failure in yield instead of buckling. By changing the specified material, Aluminium Alloy 6061-T651 to Magnesium EN-MB10020, it was revealed that vehicle mass could be reduced by an estimated 110 kg, in turn improving the fuel economy by 10 per cent. This, however, would require mechanical performance compromise unless the current design is modified. Originality/value This is the first time that a comparative analysis of material substitution has been made on the Wikispeed car. The results of such work will assist in the lowering of harmful greenhouse gas emissions and simultaneously augment fuel economy

An economic evaluation of tailor welded blanks in automotive applications

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1997.Includes bibliographical references (leaves 69-74).by Anna M. Lokka.M.S

Cost, range anxiety and future electricity supply: A review of how today's technology trends may influence the future uptake of BEVs

In this review paper, we show that the current battery electric vehicle (BEV) scale-up relies on several key technologies which all have detailed roadmaps with good track records for being met. These roadmaps include lightweighting of vehicle bodies using lightweight materials and architecture/structure design, and improvements in BEV powertrain with regard to the powertrain architecture/system design, battery and motor technology development. However, as technology take-up accelerates, our novel analysis suggests supply of zero carbon electricity may become a serious constraint. We find that the technical potential for abating the demand for electricity through powertrain and lightweighting improvements is just over a quarter of the projected total. Four promising avenues to mitigating this constraint – battery reusing and interoperable charging technology, shared mobility, advanced sensing technology, and novel compact space frame construction - are explored in brief, potentially enabling the large-scale deployment of BEVs without exhausting the supply of non-emitting electricity

A preliminary mechanical design evaluation of the Wikispeed car: for light-weighting implications

Purpose Road passenger transportation faces a global challenge of reducing environmental pollution and greenhouse gas emissions because of the vehicle weight increases needed to enhance passenger safety and comfort. This paper aims to present a preliminary mechanical design evaluation of the Wikispeed Car (with a focus on body bending, body torsion and body crash) to assess light-weighting implications and improve the vehicle’s environmental performance without compromising safety. Design/methodology/approach For this research, finite element analysis (FEA) was performed to examine the Wikispeed chassis for light-weighting opportunities in three key aspects of the vehicle’s design, namely, for body bending the rockers (or longitudinal tubes), for body torsion (again on the rockers but also the chassis as a whole) and for crash safety – on the frontal crash structure. A two-phase approach was adopted, namely, in phase one, a 3D CAD geometry was generated and in phase, two FEA was generated. The combination of analysis results was used to develop the virtual model using FEA tools, and the model was updated based on the correlation process. Findings The research revealed that changing the specified material Aluminium Alloy 6061-T651 to Magnesium EN-MB10020 allows vehicle mass to be reduced by an estimated 110 kg, thus producing a concomitant 10 per cent improvement in fuel economy. The initial results imply that the current beam design made from magnesium would perform worst during a crash as the force required to buckle the beam is the lowest (between 95.2 kN and 134 kN). Steel has the largest bandwidth of force required for buckling and also requires the largest force for buckling (between 317 kN and 540 kN). Originality/value This is the first study of its kind to compare and contrast between material substitution and its impact upon Wikispeed car safety and performance

Life Cycle Energy Assesment of Advanced Fiber Reinforced Composite Design and Manufacturing Methodologies

Automotive industry at large is focused on vehicle light-weighting since a 6%-8% increase in fuel efficiency can be achieved with a 10% reduction in vehicle weight [1]. With the growing demand for cost-effective and sustainable light weighting of automobile structures, interest has increased in the application of fiber reinforced plastic (FRP) composites for use in the Body-in-White (BiW), which can account for up to 40% of the total vehicle weight. Traditional FRP composite manufacturing processes like vacuum assisted resin transfer molding, autoclave consolidation or use of automated fiber placement have been successfully used for marine and aerospace applications. However, these processes are not suitable for the automotive industry due to the low production rate, need for highly skilled labor for manufacturing and quality control, and poor joining with traditional structural materials like steel. This necessitates the use of higher throughput outof-autoclave (OOA) processes like high pressure resin transfer molding (HP-RTM), wet compression molding (WCM) or even fiber reinforced thermoplastics (FR-TP) forming. The transition to these OOA processes face two major challenges: a) the time-consuming iterative design and thermal profiling process required for metal tools which increases cost; and b) the lack of a low-cost, scalable, and sustainable multi-material joining pathways that can enable integration of FRP composite parts with traditional metal structures. This is because existing composite joining methods necessitate significant redesign of existing OEM infrastructure, incur high capital costs, and produce weak joints between metal and composite components. iii To address the first challenge, a new paradigm where additive manufacturing of thermoplastic filament reinforced with continuous fiber is used to develop a low-cost and sustainable composite tool, is investigated. Furthermore, additive manufacturing can enable faster tool design turn-around times and allows for designing of complex tool geometries with embedded sensors and conformal cooling channels. This opens greater avenues for process and design optimization and will enable manufacturers to gain a better understanding of the process based on sensor data gathered in real time from the embedded sensors. To address the later challenge, a highly integrated multi-material, FRP-intensive BiW design was developed using unique multi-material transition joints which retain existing OEM joining infrastructure [2]. It incorporates multi-material transition joints where continuous dry fibers are laid through machined looped channels in a metal substrate and additional metal layers are additively manufactured on top of the looped fiber and metal substrate to embed the fibers within the metal and create a strong metal – fiber mechanical interlocking bond. The fibers are then infused with a thermoset matrix that fills out the loops as well, forming a string FRP-metal transition [3]. Thus, the resulting CFRP component with metal tabs can be spot welded to other metal components without piercing, drilling, or punching holes - significantly increasing the mechanical performance of the multi-material joints. To ascertain the advantages of these multi-material designs and the use of state-of-the-art additively manufactured smart tools, their life cycle impact must be investigated and compared with existing technology. The results from the LCA can provide vital understanding of the energy requirements of the new processes methodologies and can help iv quantify the benefits offered by transitioning to this new proposed paradigm of composite design and manufacturing from a sustainability and emission reduction standpoint. To best of the authors knowledge there have been no studies that address the LCA for each of the proposed solutions. Thus, this work, conducts two comparative life cycle analyses on the proposed additively manufactured smart composite tool for OOA processes and for the multi-material designs for automotive structural components. Different scenarios are studied for both the LCAs to consider the existing FRP production processes as well as the production process of traditional materials

Lightweighting of double-decker buses

The bus industry is currently undergoing extensive transformation as cities around the world push for the rapid introduction of electric buses. Lightweighting of bus structures is identified by leading experts as one of the key technologies necessary to enable and assist this revolution in the industry. Alexander Dennis Ltd. (ADL) is the UK’s largest bus manufacturer and a worldwide leader in the construction of double-decker buses. ADL consider lightweighting to be one of the three main technological pillars of the company and have thus supported various ongoing research programmes with this EngD research programme funded in collaboration with WMG, University of Warwick. This thesis summarises the outcomes of the EngD programme, the primary objective revolving around the identification of innovative yet feasible lightweighting opportunities applicable to ADL double-decker buses. A systematic review of the state-of-the-art of bus lightweighting followed by a critical analysis of ADL bus structures led to initial feasibility studies of various lightweighting opportunities which in turn led to a lightweighting proposal. An innovative lightweight upper-deck structure design was conceived, developed and proposed to ADL. The holistic redesign of the system achieved a 42% weight reduction whilst also significantly lowering the bus centre of gravity hence enabling further lightweighting of other primary structures. The redesigned upper-deck structures necessitates the novel introduction into the bus industry of two key technologies necessary for its realisation; braided fibre reinforced polymer beam structures and coated polycarbonate glazing. A study on the feasibility of utilising fibre reinforced composites to manufacture cost-effective curved structural beams was carried out. A state-of-the-art review identified a composite manufacturing process consisting of a bladder-assisted consolidation of braided commingled thermoplastic preforms as ideally suited for the bus industry. Tooling was designed and machined to allow demonstrator beams to be manufactured using the proposed method. A finite-element methodology, that would enable the design of these composite beam structures, was proposed and verified though correlation of simulation performance data with data collected from three point bend tests carried out on test beam structures. Design guidelines including considerations of manufacturing volumes and costs were prepared for use by ADL. Investigations on the feasibility of polycarbonate glazing application within the bus industry identified gaps in the knowledge of lifetime performance of polycarbonate glazing exposed to bus industry specific conditions. A novel testing set-up was designed to assess the performance of commercially available coated polycarbonate glazing exposed to a harsh daily bus washing environments. Following the successful identification of a suitable coating system, a demonstrator manufacture programme was set-up. This led to the successful manufacture and planned installation on in-service buses of polycarbonate glazing panels achieving 57% component weight reduction when compared to the current laminated-glass glazing panel

Comprehensive examination of automotive product impact. A look ahead in light of sustainable development challenges: the Magneti Marelli S.p.a business case.

Sustainable development imperatives drive industrial selection in the field of product development. Indeed, automotive productiveness plays a key-role in the worldwide trend for the transition towards a more environmentally friendly, economically affordable and socially sustainable balance. In the last few years automotive industry has been rapidly changed due to the increasingly concerned about resource depletion and GHG emissions generation. In this framework, actions addressed to reduce automotive impact has increased. To meet environmental improvement expectation a new design mind-set formula is necessary to integrate environmental attribution to component characteristic: the life cycle thinking approach. In this way, the selection of design for environment strategy is based on a balance between technological, manufacturing and sustainability aspect without shifting environmental consequences beyond company area. Magneti Marelli© Spa as a part of automotive sector has started to be committed on sustainability programs in order to reduce the impact caused by its product on the environment. The Company adopted a methodology, modeled on proposals made by scientific institutes, for the creation of its own system, devoted to obtain results, which could be measurable, understandable and implementable to their strategic plan. The well-recognized Life Cycle Sustainability Assessment methodology, was used and adapted to the company’s context for R&D applications and purposes. This effort was accomplished with the collaboration of company members at different levels (R&D, purchase, logistics, innovation) and with the stakeholders’ collaboration (suppliers of materials and semi-products, EoL management companies and vehicle users) and resulted in over fourteen projects which introduced a wide array of innovative materials, processes and technological applications. The outcome of these projects have enriched the company’s knowledge and have become the basis for more conscious and strategic choices for achieving goals relating to a reduction in product impact, thus helping to protect the planet while guaranteeing company development and progress