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The Composite Lightweight Automotive Suspension System is a composite rear suspension knuckle/tieblade consisting of UD prepreg (epoxy resin), SMC (vinylester resin) carbon fibre and a steel insert to reduce the weight of the component by 35% and reduce Co2. The compression moulding manufacturing process and CAE optimisation are unique and ground-breaking for this product and are designed to allow high volume manufacture of approx. 30,000 vehicles per year. The manufacturing techniques employed allow for multi-material construction within a five minute cycle time to make the process viable for volume manufacture. The complexities of the design lie in the areas of manufacturing, CAE prediction and highly specialised design methods. It is a well-known fact that the performance of a composite part is primarily determined by the way it is manufactured.

Magnesium die-cast alloys are known to have a layered microstructure composed of: (1) An outer skin layer characterized by a refined microstructure that is relatively defect-free; and (2) A “core” (interior) layer with a coarser microstructure having a higher concentration of features such as porosity and externally solidified grains (ESGs). Because of the difference in microstructural features, it has been long suggested that removal of the surface layer by machining could result in reduced mechanical properties in tested tensile samples. To examine the influence of the skin layer on the mechanical properties, a series of round tensile bars of varying diameters were die-cast in a specially-designed mold using the AM60 Mg alloy. A select number of the samples were machined to different final diameters. Subsequently, all of the samples (as-cast as well as machined) were tested in tension.

Due to magnesium alloy's poor weldability, other joining techniques such as laser assisted self-piercing rivet (LSPR) are used for joining magnesium alloys. This research investigates the fatigue performance of LSPR for magnesium alloys including AZ31 and AM60. Tensile-shear and coach peel specimens for AZ31 and AM60 were fabricated and tested for understanding joint fatigue performance. A structural stress - life (S-N) method was used to develop the fatigue parameters from load-life test results. In order to validate this approach, test results from multijoint specimens were compared with the predicted fatigue results of these specimens using the structural stress method. The fatigue results predicted using the structural stress method correlate well with the test results.

Motivated by a combination of increasing consumer demand for fuel efficient vehicles, more stringent greenhouse gas, and anticipated future Corporate Average Fuel Economy (CAFE) standards, automotive manufacturers are working to innovate in all areas of vehicle design to improve fuel efficiency. In addition to improving aerodynamics, enhancing internal combustion engines and transmission technologies, and developing alternative fuel vehicles, reducing vehicle weight by using lighter materials and/or higher strength materials has been identified as one of the strategies in future vehicle development. Weight reduction in vehicle components, subsystems and systems not only reduces the energy needed to overcome inertia forces but also triggers additional mass reduction elsewhere and enables mass reduction in full vehicle levels.

The Multi Material Lightweight Vehicle (MMLV), developed by Magna International and Ford Motor Company, is a result of US Department of Energy project DE-EE0005574. The project demonstrated the lightweighting potential of a five-passenger sedan while maintaining vehicle performance and occupant safety. Prototype vehicles were manufactured and limited full-vehicle testing was conducted. The Mach-I vehicle design, comprised of commercially-available materials and production processes, achieved a 364 kg (23.5%) full-vehicle mass reduction. This resulted in environmental benefits and fuel economy improvements. A significant factor in the overall MMLV mass reduction was the decrease in the powertrain system weight from 340 kg (conventional) to 267 kg (MMLV). This enabled the application of a 1.0-liter three-cylinder engine as the main powerplant. By downsizing the engine, and by implementing material changes within the engine, the weight of the dressed engine was lowered by 29 kg.

While weight reduction in automotive design and manufacturing has been on-going for several years, in the area of powertrain technology lightweighting has been a difficult challenge to overcome due to functional requirements, as well as material and manufacturing constraints. The Multi Material Lightweight Vehicle (MMLV) developed by Magna International and Ford Motor Company is a result of US Department of Energy project DE-EE0005574. The project demonstrates the lightweighting potential of a five passenger sedan, while maintaining vehicle performance and occupant safety. Prototype vehicles were manufactured and limited full vehicle testing was conducted. The Mach-I vehicle design, comprised of commercially available materials and production processes, achieved a 364kg (23.5%) full vehicle mass reduction, enabling the application of a 1.0-liter three-cylinder engine resulting in a significant environmental benefit and fuel reduction.

In present paper, the process of joining aluminum alloy 6111T4 and steel HSLA340 sheets by self-piercing riveting (SPR) is studied. The rivet material properties were obtained by inverse modeling approach. Element erosion technique was adopted in the LS-DYNA/explicit analysis for the separation of upper sheet before the rivet penetrates into lower sheet. Maximum shear strain criterion was implemented for material failure after comparing several classic fracture criteria. LS-DYNA/implicit was used for springback analysis following the explicit riveting simulation. Large compressive residual stress was observed near frequent fatigue crack initiation sites, both around vicinity of middle inner wall of rivet shank and upper 6111T4 sheet.

In this paper, the cyclic deformation behavior of an Al-Si-Cu alloy is studied under strain-controlled thermo-mechanical loading. Tests are carried out at temperatures from 20 °C to 440 °C. The effect of strain rate, hold time at temperature and loading sequence are investigated at each temperature. The results show that temperature has a significant effect on the cyclic deformation of Al-Si-Cu alloys. With increasing temperature, the effect of strain rate and hold time become more significant, while load sequence effects remain negligible within the investigated temperature range. Thus, an elasto-viscoplastic model is required for modeling the alloy's behavior at high temperature. This study provides an insight into the necessary information required for modeling of automotive engine components operating at elevated temperature.

This work demonstrates the feasibility of hot stamping a B-pillar outer panel from aluminum alloy 7075. AA7075 is characterized by a high strength to weight ratio with yield strengths comparable to those of DP and TRIP advanced high strength steels. Applications using AA7075 have typically been limited to the aerospace industry due to the high variable cost associated with forming and joining of these materials. A primary key to implementation in the automotive industry is the development of metal forming methods that produce non-compromised stamped parts at automotive manufacturing volumes and costs. This work explores the feasibility of die quenching a hot blank within a cold die as a means of delivering high strength aluminum sheet parts. A die made from kirksite was used to evaluate the hot stamping process for a B-pillar outer. After the forming/quenching operation, the parts were subjected to an artificial aging process to regain the properties of the T6-temper.

The aluminum alloy 7075-T6 has the potential to be used for structural automotive body components as an alternative to boron steel. Although this alloy shows poor formability at room temperature, it has been demonstrated that hot stamping is a feasible sheet metal process that can be used to overcome the forming issues. Hot stamping is an elevated temperature forming operation in which a hot blank is formed and quenched within a stamping die. Attaining a high quench rate is a critical step of the hot stamping process and corresponds to maximum strength and corrosion resistance. This work looks at measuring the quench rate of AA7075-T6 by way of three different approaches: water, a water-cooled plate, and a bead die. The water-cooled plate and the bead die are laboratory-scale experimental setups designed to replicate the hot stamping/die quenching process.

Long glass fiber reinforced (LGFR) composites have been widely used in automotive industry to reduce vehicle weight and maintain relatively high mechanical performances. Due to the injection molding process, the distribution of fiber orientations varies at different locations and through the panel thickness, resulting in anisotropic and non-uniform mechanical properties. The current practice of computer modeling of these materials is generally using isotropic properties adjusted by a certain scale factor. The effect of fiber orientation is not carefully considered due to the complexity of fiber orientation distribution in the LGFR parts. The purpose of this paper is to identify key factors affecting vehicle attribute performances where LGFR composites are used; and provide an efficient way for accurate CAE modeling of LGFR composites. In this study, tensile coupons cut from a simple geometric injection molded plaque are tested.

Automakers have the opportunity to utilize bio-based composite materials to lightweight cars while replacing conventional, nonrenewable resource materials. In this study, Life Cycle Assessment (LCA) is used to understand the potential benefits and tradeoffs associated with the implementation of bio-based composite materials in automotive component production. This cradle-to-grave approach quantifies the fiber and resin production as well as material processing, use, and end of life for both a conventional glass-reinforced polypropylene component as well as a cellulose-reinforced polypropylene component. The comparison is calculated for an exterior component on a high performance vehicle. The life cycle primary energy consumption and global warming potential (GWP) are evaluated. Reduced GWP associated with the alternative component are due to the use of biomass as process energy and carbon sequestration, in addition to the alternative material component's lightweighting effect.

High ductility cast aluminum alloys are seeing more use in vehicles as a greater effort is made to replace components made from heavier steel and iron alloys with lighter weight alloys such as aluminum. High ductility cast aluminum has significant advantages by allowing for complex shape and considerable consolidation of parts in body structures. However, joining can be a challenge because one popular method for aluminum joining, self-piercing riveting (SPR), requires a ductility of greater than 10%, forcing the common high ductility Al alloys to undergo a T6 heat treatment which adds cost and potential distortion issues to Al component. In this study, friction stir spot welding was investigated as a potential joining technique for this material in the as-cast condition. Samples of as-cast Aural-2™ alloy were joined to Aural-2™, 5754, and 6061 alloys, to determine the manufacturing feasibility, weld strength, and fatigue strength using this joining technique.

This research focuses on study of feasibility of using ceramic oxide coatings on the cylinder wall of hypoeutectic aluminum silicon alloy engine blocks. Coatings are achieved in an aqueous electrolytic bath and composed of both alpha and gamma phases of Al2O3 and have shown promising wear resistance. Composition and acidity level of the electrolyte creates a variation of surface roughness, coating hardness and thickness which has direct influence on the wear behavior of the sliding surfaces. The effect of load bearing and coating morphology on coefficient of friction was studied. SEM images of the substrate showed no predominant wear behavior or delamination. Coefficient of friction and wear rate were also measured. This study shows the importance of surface structure on oil retention and wear rate. Coarser coatings can be desirable under starved oil condition since they show lower coefficient of friction.

The pneumatic air brake system for heavy commercial trucks is composed by a large number of components, aiming its proper work and compliance with rigorous criteria of vehicular safety. One of those components, present along the whole vehicle, is the air brake tube, ducts which feed valves and reservoirs with compressed air, carrying signals for acting or releasing the brake system. In 2011, due to a lack of butadiene in a global scale, the manufacturing of these tubes was compromised; as this is an important raw material present on the polymer used so far, PA12. This article introduces the methodology of selecting, developing and validating in vehicle an alternative polymer for this application. For this purpose, acceptance criteria have been established through global material specifications, as well as bench tests and vehicular validation requirements.

A demonstration structure was cast in AM60. The structure, known as the Generic Frame Casting or GFC, was designed specifically to mimic features seen in castings for closure applications. Excised samples were subsequently removed from different areas of the casting and tested under axial loading conditions. Component level tests were also conducted. Comparison of the excised sample results and the component level testing indicated the influence of local properties on the component level deformation. It was shown that varying the casting processing conditions could change the local ductility and yield strength in different areas of casting with the same geometry. Lowering the local ductility decreased the total displacement in a component level test and lowered the amount of energy absorption. Therefore, understanding the processing conditions and their influence on the local properties is important for predicting behavior in a component level test.

Magnesium alloy extrusions offer potentially more mass saving compared to magnesium castings. One of the tasks in the United States Automotive Materials Partnership (USAMP) ?Magnesium Front End Research and Development? (MFERD) project is to evaluate magnesium extrusion alloys AM30, AZ31 and AZ61 for automotive body applications. Solid and hollow sections were made by lowcost direct extrusion process. Mechanical properties in tension and compression were tested in extrusion, transverse and 45 degree directions. The tensile properties of the extrusion alloys in the extrusion direction are generally higher than those of conventional die cast alloys. However, significant tension-compression asymmetry and plastic anisotropy need to be understood and captured in the component design.

Magnesium alloys are the lightest structural metal and recently attention has been focused on using them for structural automotive components. Fatigue and durability studies are essential in the design of these load-bearing components. In 2006, a large multinational research effort, Magnesium Front End Research & Development (MFERD), was launched involving researchers from Canada, China and the US. The MFERD project is intended to investigate the applicability of Mg alloys as lightweight materials for automotive body structures. The participating institutions in fatigue and durability studies were the University of Waterloo and Ryerson University from Canada, Institute of Metal Research (IMR) from China, and Mississippi State University, Westmorland, General Motors Corporation, Ford Motor Company and Chrysler Group LLC from the United States.

A task group within the SAE Automotive Corrosion and Protection (ACAP) Committee continues to pursue the goal of establishing a standard test method for in-laboratory cosmetic corrosion evaluations of finished aluminum auto body panels. The program is a cooperative effort with OEM, supplier, and consultant participation and is supported in part by USAMP (AMD 309) and the U.S. Department of Energy. Numerous laboratory corrosion test environments have been used to evaluate the performance of painted aluminum closure panels, but correlations between laboratory test results and in-service performance have not been established. The primary objective of this project is to identify an accelerated laboratory test method that correlates with in-service performance. In this paper the type, extent, and chemical nature of cosmetic corrosion observed in the on-vehicle exposures are compared with those from some of the commonly used laboratory tests

Creep-resistant magnesium alloys for automotive powertrain applications offer significant potential for vehicle weight reduction. In this study permanent mold casting, microstructure and creep behavior have been investigated for a series of ternary magnesium alloys (Mg-4Al-4X (X: Ca, Ce, La, Sr) wt%) and AXJ530 (Mg-5Al-3Ca-0.15Sr, wt%). A permanent mold was instrumented with twelve thermocouples and mold temperature was monitored during the casting process. Average mold temperature increased from 200°C to 400°C during a typical alloy casting series (fifteen to twenty castings). The cast microstructure for all alloys consists of primary α-Mg globular phase surrounded by eutectic structure which is composed of intermetallic(s) and α-Mg magnesium phases. The primary cell size of the AXJ530 increased from 18 to 24 μm with increasing mold temperature and a similar trend is expected for all alloys.