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The advances in computer applications have been increasing in the recent years. The applications of Artificial Intelligence (AI) in the product design software, and the advancements in the Direct Digital Manufacturing (DDM) such as Additive Manufacturing have been leading the aerospace and automobile industries into the next level. AI assisted generative design helps the designers to reduce the weight of the structures without compensating the strength of the structures. The topology optimization is one of the subsets of the generative design which commonly used by the designers to design and redesign many components for weight reduction. This article studies the applications of topology optimization for an aerospace and an automobile components for design modification and weight reduction. The prototype of the optimized components are printed using FDM 3D printing for examining the shape optimization. The stress analyses of the components are analyzed using FEM.

With the increasing need for developing fuel-efficient and high-performance vehicles, light weighting has become a very important aspect in automotive industry. Hence conversion of the existing metal components to composites is gaining momentum. Composite materials are much lighter than metals and offer many advantages such as fuel efficiency, corrosion resistance and improved life which has resulted in the increased usage of composite materials. Front under-run protection device (FUPD) is a protective device which is fitted on the front side of a truck which prevents the vehicle in front from under-running below the truck and also absorbs impact energy in case of a collision. This paper discusses the design, development and certification from ARAI of the lightweight composite front under-run protection device (FUPD). It has resulted in 33.33% weight reduction compared to the earlier metal component.

The small commercial vehicle business is driven by demand in logistic, last mile transportation and white goods market. And to cater these businesses operational and safety needs, they require closed container on vehicle. As of now, very few OEM’s provide regulatory certified container vehicle because of constrains to meet inertia class of the vehicle. This paper focuses on design of a durable and extremely reliable container, made of the low-cost economy class glass fibre & core material. The present work provides the means to design the composite container for the N1 category of the vehicle. The weight of after-market metal container ranges between 300-350 Kg for this category of vehicle, which affects the overall fuel economy and emission of the vehicle. A detailed CAE analysis is done to design composite container suitable to meet inertia class targets and to achieve weight reduction of 30-40% as compared to metal container.

According to the increasing demands for light-weight design in the automotive industry, the use of thinner and lighter materials such as aluminum alloys for automotive parts has led to significant weight reduction. The joining of these materials has required development of new technologies in joining/fastening rather than welding. Flow drill screwing is one of the latest technologies created to fasten sheet metal panels. This paper discusses results of an evaluation of fatigue characteristics of flow drill screw (FDS) joints based on experimental data and observations from the literature. It was observed that the important fatigue-related geometric parameters of FDS joints were the gap between sheets and the extruded (or bulged) zone during screwing. Major failure modes were observed such as sheet failures where cracks grow from the inner surface of the sheet and around the extruded zone.

Developing of innovative technologies and materials to meet the requirements of environmental legislation on vehicle emissions has paramount importance for researchers and industries. Therefore, improvement of engine efficiency and fuel saving of modern internal combustion engines (ICEs) is one of the key factors, together with the weight reduction. Thermoplastic composite materials might be one of the alternative materials to be employed to produce engine components to achieve these goals as their properties can be engineered to meet application requirements. Unidirectional carbon fiber reinforced PolyEtherImide (CF/PEI) thermoplastic composite is used to design engine connecting rod and wrist pin, applying commercial engine data and geometries. The current study is focused on some elements of the crank mechanism as the weight reduction of these elements affects not only the curb weight of the engine but the overall structure.

Standards organizations develop standards depending on the need in the market place. With the change in vehicle design, lightweighting structures, and body panels made out of aluminum and composites, SAE’s Acoustical Materials Committee is developing a new damping standard. This standard is also very suitable in determining the damping performance of materials used in the off-highway applications, where the thickness of the steel body panel is much greater than in the automotive application. The general methodology of this standard is based on the mechanical impedance measurement method and has been developed with the general consensus of automotive engineers, suppliers, and independent test laboratories. This method is essentially based on the fact that a bar is excited at the center by a shaker. The force exerted by the shaker and the corresponding vibration is measured at that point to determine the frequency response function of the mechanical impedance signal.

Spot Welds are a category of welds used extensively in automotive structures, normally for metals. The fatigue analysis of such spot welds can be evaluated using (a) the Point 2 Point (P2P) method where a beam or bar is used to connect the 2 surfaces being joined, (b) a more modern approach where the 1D element is replaced with an “equivalent” brick element, or (c) a third approach that falls somewhere between where a “spider” and circular ring of elements, is used to represent the spot weld. In all 3 cases there is an assumption that the cross section is circular. For some specialist cases such as plastic connectors, the cross section is not circular so a new user defined weld is proposed. This paper will describe the approach that is based on the concept that a user generated tensor line can be used (equivalent to the theoretical Force/Moment to stress algorithms built into the P2P approach) along with special S-N curves create for different joint shapes.

Efficiency and dynamic behavior of a vehicle are strongly affected by its weight. Taking into consideration comfort, safety and emissions in modern automobiles, lightweight design is more of a challenge than ever in automotive engineering. Materials development plays an important role against this background, since significant weight decrease is made possible through the substitution of high density materials and more precise adjustment of material parameters to the functional requirements of components. Reinforced light metals, therefore, offer a promising approach due to their high strength to weight ratio. The paper gives an overview on matrix and reinforcement structures suited for the high volume output of the automotive industry. Further analytical and numerical approaches to describe the strengthening effects and the good mechanical characteristics of these composite materials are presented.

This paper illustrates a methodology in which complete material-manufacturing process cases for closure panels, reinforcements, and assembly are modeled and compared in order to identify the preferred option for a lightweight closure design. First, process-based cost models are used to predict the cost of lightweighting the closure set of a sample midsized sports utility vehicle (SUV) via material and process substitution. Weight savings are then analyzed using a powertrain simulation to understand the impact of lightweighting on fuel economy. The results are evaluated in the context of production volume and total mass change.

Often electrical components are encapsulated in a plastic material after assembly. The goal of this study is to determine what variables are most important in reducing potting variation and identify the key machine parameters which can be used to make adjustments to the potting process. To maximize the efficiency of testing, an L18 orthogonal array was used to structure an experiment. Hose temperature, orifice size, and pressure were found to be the most significant control factors studied in this experiment. Shifting from the initial settings for these factors to the recommended settings should increase the S/N of the potting process by 14.53db. Motor speed was found to be the most significant variable for adjusting the mean of the process. The noise factors induced in this study were found to be a significant source of variation. Filters can shift the mean potting material applied by 25% over their planned usage life. Moreover, new filters induce more variation than old filters.

The weight reduction in vehicles is a subject of increasing importance at this moment in the automotive industry following the application of ultra high strength steels. Lightest vehicles bring material and energy economy, and also go in favor of the current environmental politics. The vehicles weight cannot be reduced without engineering changes, reason for new producing methods of lighter steel components are being developed, reducing the amount of the vehicles components. One of these techniques is the Hydroforming. Hydroforming consists in use the fluid pressure in substitution of the punch in a conventional press tooling to form the desired shape of the components. The technique is very useful to produce entire components that would be made in conventional way for multiples pressed components joined later. For example, a typical chassis set that would be normally made by up to six presses and welded components can be hydroformed as a single part.

Western Canada has large acreage of oilseed flax, but unfortunately a small percentage of total crop residue (flax straw) produced annually is being commercially used. Therefore, farmers are still burning the flax straw. Flax fiber and straw has highest strength amongst the different natural fibers, therefore, the prospect of using them as biorenewable reinforcement in recycled/ virgin polymer matrices has gained attention in recent years. Flax strawboard has a potential to replace the currently used wood and other crop like wheat/barley straw boards for different industrial application. In this research Oilseed flax straw reinforced composite boards were developed using flax shives with biopolymer binder made out of recycled/ pure thermo plastic and flax fiber. Some advantages of such materials are high strength, low density, good insulation capacity against heat and moisture transfer, and biodegradability.

The fastener analysis for an airframe panels under random cyclic loading conditions were analyzed with various elaborate solutions. But here a simple technique is proposed to analyze the problem and prove the necessity for a design solution. It is shown that the misfit in the fastener system reduces the load capacity of the joint due to the lack of contact or reduced contact. This reduced contact also produces various stress concentration at the contact zones. In the cyclic loading environment this reduced load capacity and increased stress concentration produces elastic plastic deformation around the contact locations and at the same time a crack develops and propagates beyond the fastener system. This creates a load leak transparent to the fastener system. Thus the misfit fastener systems have a higher probability of aging than the fit fasteners. With the proof in hand various design patterns were proposed to improve the fatigue characters under varying types of loading conditions.

High axial loads applied on conical roller bearings can lock the wheel hub after the fastener assembling. This assembly can be made, nowadays, using a castle nut plus a cotter pin or by plastic deformation of the nut to prevent its release. This procedure involves many components for the assembling, restrict its reuse, add extra costs, and provide possible failures during the assembling line or during the future maintenance. This work proposes to demonstrate the development of an efficient and easy system to mount wheel hubs on lines and later to assure maintenance without jeopardizing the efficiency and the functionality of the tapered roller bearing.

Several new families of expanding mandrel type of temporary (slave) fastener are in production and/or undergoing qualification tests. These fasteners are characterized by a collapsible mandrel that expands when needed over a center spindle. These fasteners are blind (installed and removed from one side only), and they provide locating (dowel) capabilities. This paper illustrates how these new fasteners work and how they are designed. Results of some testing of nominal ¼″, flush head fasteners in carbon-fiber reinforced plastic are shown. Design criteria include the temporary fasteners clamping ability, acceptable contact stresses, cyclic fatigue life, and strength.

Advanced material modeling was conducted to describe the thermal-mechanical behavior of Boron Steel during hot stamping, a process in which blanks at 900 °C are formed and quenched between cold dies. Plastic deformation, thermal dilatation and phase transformation were incorporated in the constitutive model and a user-defined subroutine was developed to interface with LS-DYNA. Simulation was conducted on the hot stamping process of a door intrusion beam to gain insight into the physics of the process. Results showed significant influence of the thermal cycle on final product. It was also demonstrated that the program developed can be used as an early feasibility tool to determine baseline processing parameters and to detect potential defects in products without physical prototyping.

In Brazil the market for plastic parts molds, in last few years had become very competitive, with several Vehicle Operations and a big number of a different models, and with today total market volume it means low volumes productions for each model. This market demands for good toolshops and at the same time a big pressure to reduce investments, one of the most important. Plastic components usage in the car, is increasing overtime, with new applications for Exterior, interior and powertrain, requiring new technologies for Injection molding processing and making molds to be more complex. The development of plastic parts in Brazil has its own characteristics, strengths and weaknesses. In fact a big and heterogeneous market. This paper intends to present an analysis of development of plastic parts in Brazil, considering the development of mold tooling locally, focusing the automotive market.

The advantages of magnetic implant induction welding (Emabond™)1 technology for various thermoplastics were widely discussed since the mid-eighties in a series of technical articles and reports, and presented to the professional Societies (SAE, SPE, SME, etc). In 1998-2003, we reported to SAE International our technical achievements in optimizing the mechanical performance of welded nylon (6, 66, 6/66, 46, etc.) using frictional (linear and orbital vibration, ultrasonic), contact (hot plate), and non-contact (laser through-transmission) welding technologies. Our recent developments focused on optimization of mechanical performance of induction welded nylon 6, which has reached a new performance level through continuous improvement of magnetic implant induction welding technology, including properties of the formulated magnetic implant material, new equipment, SPC process control, optimized design of joints, etc.

Thermoplastics have been used increasingly for automobile components for both interior and under-the-hood applications. The plastic parts are made through various molding process such as compression molding, injection molding and blow molding. For parts with large or complicated geometry, small portions of the part may have to be molded first, then joined together using a welding process. The welded regions usually exhibit inhomogeneous and inferior mechanical performance compared to the bulk regions due to the differences in thermal history. The microstructures and mechanical properties of welded thermoplastics have been examined using hot-plate welded polyethylene. The specimens are prepared at various thermal conditions to simulate the real welding process. The thermal properties in welds are monitored using DSC (Differential Scanning Calorimetry) and the crystallinities are calculated.

This paper examines some processing and design factors which affect the impact performance of cast A356 aluminum wheels, as measured by SAE J175 (13° lateral impact test). Wheel impact performance is discussed with respect to two different failure criteria: (a) failure due to cracking in the hub or spokes, and (b) failure due to total loss of tire air pressure. The general influence of heat treatment on impact behavior is described, and then examined in light of a particular wheel example. Peak-aging heat treatments are compared with underaging treatments, in terms of the critical link between processing, material properties of strength and ductility, and their influence on wheel impact behavior. The effects of the rim flange geometry and other design features are then explored, and illustrated with examples.