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Hot metal gas forming (HMGF) is a desirable way for the automotive industry to produce complex metallic parts with poor formability, such as aluminum alloys. A simple hot gas forming method was developed to form aluminum alloy tubes using flame heating. An aluminum alloy tube was heated by a flame torch while the tube was rotated and compressed using a lathe machine and simultaneously pressurized with a constant air pressure. The effects of the internal pressure and axial feeding on expansion and wall thickness distribution were examined. The results showed that the proposed gas forming method was effective for forming aluminum alloy tubes. It was also indicated that axial feeding is a vital parameter to prevent reductions in wall thickness by supplying the material flow during the forming process. [ABSTRACT FROM AUTHOR]

Despite a relatively young history, metal foams have had an extensive impact on the industry. With ties to military defense, automobile safety, and jet engine sound dampening, metal foams have been optimized to successfully withstand strenuous circumstances. Applications of metal foams in the industry have led to increased safety, superior mechanical properties, and versatility in recent years. This research paper specifically looks at the sound dampening and energy absorption qualities of aluminum A356 foam, through compression and acoustic testing. [ABSTRACT FROM AUTHOR]

Hypereutectic Al-18 wt pct Si alloy is widely used in automotive industry as a wear-resistant alloy for engine components. However, in the last few years, this traditional composition is being considered for processing by different rapid solidification methods. Positive points include its low thermal expansion and uniform distribution of surface oxides. Nevertheless, the microstructural aspects of Al-Si powders of 18 wt pct Si are still need to be addressed, such as, the eutectic Si morphology, size, and distribution generated by different process conditions during rapid solidification. Based on a detailed quantitative analysis of the microstructures of rapid solidified Al-18 wt pct Si in this work, solidification conditions that yield specific Si morphologies, Si spacing, and thermal cooling conditions are outlined. The focus is determining the solidification conditions that will yield a specified shape of eutectic Si. It is shown that Si morphology is dependent on a combination of growth velocity (based on modified JH model) and temperature gradient. Furthermore, the highest hardness is achieved with globular morphologies of Si. The processing conditions required to achieve these properties are outlined. [ABSTRACT FROM AUTHOR]

Aluminum use is growing in automotive closures and body in white applications to improve vehicle performance and fuel economy. The auto industry is looking for higher-strength aluminum materials needed for strength-driven safety-critical parts. Through cooperation with industrial partners and support from the Department of Energy (DOE), multiple experimental 7xxx alloys were developed for automotive applications. The objective is to enable complex shapes to be formed at temperatures below 225°C. A demonstration part has been developed that is representative of the forming challenges within a current hot-stamped door ring component. This part tooling has been built and installed into a press line which includes blank heating and robotic transfer. Forming trials of these alloys are currently underway and the formability, strength and corrosion performance of these materials are being evaluated. [ABSTRACT FROM AUTHOR]

Constructions of steel sheets and sheets from aluminium alloys are widely used in car body production to reduce the total car weight. The reduction in car weight is needed to improve fuel efficiency. Aluminium alloys play a more important role in future car body generations. Properties of this material give some advantages and open the way for new applications in the automotive industry. It is not possible to join the multiply material combination by conventional joining methods such as resistance spot welding. Therefore, alternative joining methods are being developed. One of the alternatives is mechanical joining -- clinching. Clinching is suitable for joining the thin sheets from ferrous and non-ferrous metals. Mechanical clinching is also well known as a speed and efficient cold joining process, mainly for joining the thin-sheet applications. In this process, the local plastic deformation of the sheets is created by the clinching tool. The paper focuses on the evaluation of the properties of mechanically clinched joints, realized on the combination of the zinc-coated steel sheets DC06 and H220PD and sheets from aluminium alloys EN AW 5754 with various hardness H11, H22 and H24 and EN AW 6082. The tensile test and a metallographic observation were used to evaluate the clinched joint properties. Mechanical clinching proved to be suitable technique for joining the observed combination of steel sheets and aluminium alloy sheets. It is necessary to consider the orientation of the sheets relative to punch and die. [ABSTRACT FROM AUTHOR]

The aim of this work is to create material model for aluminum material AW 5754 H11 for numerical simulation, which is widely used in automotive industry. For purpose of verification material model the deep drawing cup test was carried up, and measured parameters were punch force, thickness distribution and ear profile. Results from numerical simulation were validated by real experiment with regard to predict accuracy in changes of thickness and ear profile. [ABSTRACT FROM AUTHOR]

Aluminum and alloys are widely used in the automotive industry due to the light weight, good formability, and malleability. Spot welding is the most commonly used joining method of these materials, but the high current requirements and the inconsistent quality of the final welds make this process unsuitable. An alternative welding technique, the friction-stir spot welding process, can also be successfully used in joining of aluminum and alloys. In this study, 1-mm-thick AA5754 Al-alloy plates in the H-111 temper conditions were joined by friction-stir spot welding using two different weld parameters such as tool rotational speed and dwell time. Mechanical properties of the joints were obtained with extensive hardness measurements and tensile shear tests. The effect of these parameters on the failure modes of welded joints was also determined. [ABSTRACT FROM AUTHOR]

Aluminum recycling currently occurs in a cascading fashion, where some alloys, used in a limited number of applications, absorb most of the end-of-life scrap. An expected increase in scrap supply in coming decades necessitates restructuring of the aluminum cycle to open up new recycling paths for alloys and avoid a potential scrap surplus. This paper explores various interventions in end-of-life management and recycling of automotive aluminum, using a dynamic substance flow analysis model of aluminum and its alloying elements with resolution on component and alloy level (vehicle-component-alloy-element model). It was found that increased component dismantling before vehicle shredding can be an effective, so far underestimated, intervention in the medium term, especially if combined with development of safety-relevant components such as wheels from secondary material. In the long term, automatic alloy sorting technologies are most likely required, but could at the same time reduce the need for magnesium removal in refining. Cooperation between the primary and secondary aluminum industries, the automotive industry, and end-of-life vehicle dismantlers is therefore essential to ensure continued recycling of automotive aluminum and its alloying elements. [ABSTRACT FROM AUTHOR]

Abstract: Light weight aluminum has shown high applicability in the automobile industry for high fuel efficiency. However, the manufacturing of aluminum is limited by the deburring process owing to the difficulty in employing wet blasting. In this paper, we present experimental and computational studies on the deburring process of wet blasting for aluminum. The process conditions are analyzed to achieve high deburring performance that minimizes the surface damage. Parameters of wet blasting with a significant influence on the deburring process are investigated and a promising deburring technique for aluminum is proposed. [Copyright &y& Elsevier]

Replacing conventional materials (steel and iron) with lighter alternatives (e.g., aluminum, magnesium, and composites) decreases energy consumption and greenhouse gas (GHG) emissions during vehicle use but may increase energy consumption and GHG emissions during vehicle production. There have been many life cycle assessment (LCA) studies on the benefits of vehicle lightweighting, but the wide variety of assumptions used makes it difficult to compare results from the studies. To clarify the benefits of vehicle lightweighting we have reviewed the available literature (43 studies). The GHG emissions and primary energy results from 33 studies that passed a screening process were harmonized using a common set of assumptions (lifetime distance traveled, fuel-mass coefficient, secondary weight reduction factor, fuel consumption allocation, recycling rate, and energy intensity of materials). After harmonization, all studies indicate that using aluminum, glass-fiber reinforced plastic, and high strength steel to replace conventional steel decreases the vehicle life cycle energy use and GHG emissions. Given the flexibility in options implied by the variety of materials available and consensus that these materials have substantial energy and emissions benefits, it seems likely that lightweighting will be used increasingly to improve fuel economy and reduce life cycle GHG emissions from vehicles. [ABSTRACT FROM AUTHOR]

The recent emphasis on more reliable life predictions for fatigue-critical parts in ground vehicles would result in a reduction in costly and time-consuming traditional component testing practices. This paper aims at implementing experimental and predictive durability approaches to vehicle suspension components. Forged steel and cast aluminium steering knuckles were chosen as typical components. The fatigue behaviours of components were investigated via constant-amplitude load-controlled fatigue tests. Finite element models of the knuckles were analysed using linear and non-linear methods. Nominal stress, local stress, and local strain life prediction approaches were employed and compared with experimental results to evaluate the accuracy and validity of these approaches. The strengths and shortcomings of the applied models and the alternative analysis techniques are discussed. It is shown that among the contemporary life prediction procedures used in the automotive industry, the local strain approach in conjunction with the plasticity-corrected simple elastic analysis procedure yields reasonable life predictions that are typical of more complex and much more time-consuming non-linear analysis. A number of complexities such as material property variability, variable-amplitude and multiaxial loadings, manufacturing parameters, and environmental effects on durability assessment are also discussed. [ABSTRACT FROM AUTHOR]

This study presents results concerning the stiffness and denting resistance of 6111-T4 aluminium alloy and AZ31B-H24 magnesium alloy. Experimental results of dynamic denting are compared with numerical simulations performed using LS-DYNA software. The experimental tests were performed on 0.9 and 1.09 mm thick plates clamped in a circular area with a diameter of 80 mm. Dynamic denting was accomplished by dropping different indenters from heights ranging from 0.36 to 1.7 m. The obtained experimental results enabled the properties of the two light alloys tested to be compared. The results of the numerical simulations display a good correlation with experiments if dynamic effects are introduced into the constitutive equation of the material through the Cowper-Symonds coefficients. [ABSTRACT FROM AUTHOR]

Dendritic microstructures control the properties of a wide range of advanced materials ranging from nickel-based superalloys used in turbine blades to lightweight aluminum-based alloys for the automotive industry. This article reviews recent progress in quantitative modeling dendritic growth through the combination of state-of-the-art atomistic and phase field simulations. Also shown is how the combination of these two distinct length-scale modeling approaches can yield a parameter-free prediction of the dendrite growth velocity as a junction of undercooling for deeply undercooled nickel melts. [ABSTRACT FROM AUTHOR]

This paper describes an integrated structural optimization procedure using a multilevel decomposition technique and a domain mapping contour that can represent the production parameter region. At the upper level, the structural responses are represented in terms of global quantities, i.e. stiffness, stresses and weight. At the lower level, the structural responses are represented in terms of local quantities, i.e. the intermediate parameters or the detailed dimensions based on the production parameter region. This technique was applied to develop the aluminium vehicle structure. The crosssectional characteristics and joint stiffness of the vehicle structure are calculated from the vehicle structure model which is composed of shell–beam–spring elements. In comparison with the base model (steel structure), the bending stiffness and torsional stiffness of the developed aluminium vehicle structure increase by around 45 and 35 per cent respectively, and the weight reduction is around 30 per cent. The manufactured structure is also presented. [ABSTRACT FROM AUTHOR]

A chromium-free surface treatment method was developed for aluminum bodies. By adding fluorine ions and iron complex compounds to the current zinc phosphate pretreatment bath, an improved zinc phosphate film is formed on aluminum. Also, increasing the manganese in the pretreatment bath improves the alkaline resistance properties of the zinc phosphate film. As a result of these changes, the zinc phosphate film has improved secondary adhesion after water conditioning and improved filiform corrosion resistance without using a chromium rinse. Therefore, chromium can be eliminated from the paint process of aluminum bodies. This, in turn, reduces environmental burdens previously posed. [Copyright &y& Elsevier]

The use of aluminum alloys in automobile production is growing as automakers strive to lower vehicle fuel consumption and reduce emissions by substituting aluminum for steel. The current recycling infrastructure for end-of-life vehicles is mature, profitable, and well suited to steel-intensive vehicles; increased use of cast and wrought aluminum, however, will present new challenges and opportunities to the disassembler and shredder, who now comprise the first stages of the vehicle recycling infrastructure. Using goal programming techniques, a model of the auto recycling infrastructure is used to assess the materials streams and process profitabilities for several different aluminum-intensive vehicle (AIV) processing scenarios. The first case simulates the processing of an AIV in the current recycling infrastructure. Various changes to the initial case demonstrate the consequences to the disassembler and shredder profitabilities whenever the price of nonferrous metals changes; greater fractions of the vehicle are removed as parts; the parts removed by the disassembler have increased aluminum content; the quantity of polymer removed by the disassembler is increased; the disassembly costs increase; the disposal costs for shredder residue and hazardous materials increase; the shredder processing costs increase; and different AIV designs are considered. These profits are also compared to those achieved for a steel unibody vehicle to highlight the impact of introducing AIVs into the existing infrastructure. Results indicate that the existing infrastructure will be able to accommodate AIVs without economic detriment. [ABSTRACT FROM AUTHOR]