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2002-07-09
Technical Paper
2002-01-2010
Florian Wagner, Michael Kreimeyer, Gerd Sepold
The combination of dissimilar material combinations is a challenging goal for the development of parts with locally optimized properties. The main goal of these developments are weight reduction, properties optimization or the tailoring of properties for specific applications in combination with an efficient joining technology. However, using conventional high temperature joining technologies the formation of intermetallic phases within the joining zone is a nearly unavoidable phenomenon when joining dissimilar material combinations. These phases cause a lack of the mechanical stability in the joining zone. By using an optimized laser joining technology for thin sheet materials this problem could be overcome. The localized energy input of the laser beam and a controlled heat distribution leads to minimized interaction of the joint materials. To overcome process instabilities special working heads were developed.
2002-07-09
Technical Paper
2002-01-2011
Val A. Kagan
Previously we reported to the SAE 2000 basics in selection of various colored and un-colored/natural nylon 6 (polyamide - PA 6) based plastics for laser welding technology. Later we presented to Antec1 2001 and to SAE 2002 our developments of colored in black through-transmissible grades of PA 6 plastics, which were specially tailored for the specifics of the design and laser welding technology. In this current paper, we will try to enhance the understanding of the engineering community regarding the usefulness and applicability of laser welding technology, developed colored thermoplastics, and its increasing use in various automotive and transportation applications.
2002-07-09
Technical Paper
2002-01-2009
Michael Kreimeyer, Florian Wagner, Gerd Sepold, Marion Joly, Bernard Criqui
The use of high power laser sources (CO2) enables the joining of aluminum and zinc-coated steel sheets in butt configuration, using a combined welding-brazing process. Comparable to conventional thermal joining technologies, like resistance spot welding, intermetallic phases are formed in the contact zone leading to a decrease of the mechanical properties of the joint. With locally restricted energy input and high joining speeds the formation of these phases can be minimized to a none critical level. For the characterization of the seam morphology optical, X-ray and electron microscopy examinations have been carried out, demonstrating a phase layer thickness of about 2 μm. In mechanical tests, fracture stresses of 144 N/mm2 have been achieved.
2002-07-09
Technical Paper
2002-01-2007
Magdalena Les, Zbigniew Les
For many years, time series analysis methods have been applied to develop models linking serious road crashes with the effects of socio-economic and other factors. Classical time series models, such as log-linear regression or ARIMA, are useful in describing observed road trauma but are typically poor when used for forecasting road safety trends. In recent years, a new method of forecasting has been developed called an artificial neural network (ANN). The main focus of this research was on examining the possibility of using ANNs for prediction and to find complex relationships ‘hidden’ in time series models that classical modelling techniques often fail to reveal. Application of structural time series models for this purpose was also investigated.
2002-07-09
Technical Paper
2002-01-2006
Richard J. Gerth, Jay Baron, Emilio Brahmst, Steve Geddes
A comparative benchmarking study of the dimensional door quality 14 vehicles from Ford, General Motors, Daimler-Chrysler, Toyota, Nissan, BMW, Volvo, and Renault was conducted. Various aspects of the door design, manufacturing, assembly and hanging system were studied. This paper focuses on the dimensional quality of the doors and relates it to the final vehicle quality in terms of gaps and flush as well as customer satisfaction as established by J. D. Power Initial Quality Survey (IQS). For confidentiality reasons, all vehicles in the study are referred to by a coded designation.
2002-07-09
Technical Paper
2002-01-2005
Emilio Brahmst, Richard Gerth, Jay Baron, Steve Geddes
This paper discusses the results of a door benchmark study performed on 14 vehicles. The major focus is on the selection of datums or reference points and its impact on the product quality of the door system. The results indicate that there can be a relationship between datum utilization and quality metrics at any stage in the production process. Specific examples show the impact of various strategies on product performance.
2002-07-09
Technical Paper
2002-01-2002
Ioana Vasilescu, Marius Vasilescu
The experimental researches made to settle the behaviour at cold plastic deformation of Al-Li alloys used in aeronautical constructions was realized on anneal samples through upsetting, rolling, drawing and torsion methods. The aim of this paper is to determined the behaviour at cold plastic deformation and the maximum possible degree of deformation, until don't appear cracks, through these four methods presented above for some Al-Li base alloys. By examination of the results obtained through these methods, it was determined the maximum possible degree of deformation until don't appear cracks and the equations which describe the behaviour of the tested alloy to cold plastic deformation.
2002-07-09
Technical Paper
2002-01-2004
Asif A. Rizvi
The main element of dimensional management is specification cascading where customer requirements are translated into dimensional targets. It also includes GD&T, datum strategy, and tolerance optimization. These elements can only be effective if all of the work is done concurrently among various disciplines of an organization that have a stake in the fit, finish, and performance of the final product. When setting static dimensional goals during product development, vehicle performance targets and dynamic goals have to be defined simultaneously. One example is of the final door appearance for gaps and flushness on an automotive body from static standpoint. The wind-noise and door flutter are examples of dynamic performance goals. It becomes very costly to fix static fit and finish issues caused by the dynamic state of the vehicle late into the product development cycle or at the customer locations.
2002-07-09
Technical Paper
2002-01-2012
D. Daniel, J. L. Hoffmann, G. Plassart, J. Prunier
Important design requirements for an outer autobody panel are stiffness and dent resistance performance which depend on panel geometry and mechanical properties of the sheet. Specific grades of PECHINEY 6016, named as DR for « dent resistance », were designed for enhanced strengthening during paint baking. An experimental program was carried out to relate panel thickness and strength to both stiffness and dent resistance in quasi-static and dynamic (10-15km/h) conditions. Tests were performed on non prestrained flat and curved 6016 panels of different thicknesses and paint bake strengths. Steel grades and thicknesses typical of outer panels were used for comparison. Local stiffness, independent of strength, was confirmed to increase with panel curvature and sheet thickness. Static and dynamic dent resistance, which increase with sheet thickness and strength, were found to depend on panel curvature.
2002-07-09
Technical Paper
2002-01-1987
Hong Jae Yim, Sang Beom Lee, Sung Don Pyun
In this paper, an optimization technique for thin walled beams of vehicle body structure is proposed. Stiffness of thin walled beam structure is characterized by the thickness and typical section shape of the beam structure. Approximate functions for the section properties such as area, area moment of inertia, and torsional constant are derived by using the response surface method. The approximate functions can be used for the optimal design of the vehicle body that consists of complicated thin walled beams. A passenger car body structure is optimized to demonstrate the proposed technique.
2002-07-09
Technical Paper
2002-01-1988
Jan P. Löwenau, Martin H. Strobl
The Advanced Lighting Simulation (ALS) is a development tool for systematically investigating and optimizing the Adaptive Light Control (ALC) system to provide the driver with improved headlamps and light distributions. ALS is based on advanced CA-techniques and modern validation facilities. To improve night time traffic safety the BMW lighting system ALC has been developed and optimized with the help of ALS. ALC improves the headlamp illumination by means of continuous adaptation of the headlamps according to the current driving situation and current environment. BMW has already implemented ALC prototypes in real vehicles to demonstrate the advantages on the real road.
2002-07-09
Technical Paper
2002-01-1989
Rainer Neumann
Within the last decade we have noticed considerable improvements in Automotive lighting devices. Xenon headlights, Systems with low beam and high beam out of one Xenon bulb, so called Bi-Function headlights and in the near future, advanced front lighting systems (AFS) will lead to an important contribution in terms of safety when driving at night. In parallel the philosophy of automotive engineering has changed from individual technical solutions contributing to improved value within the vehicles to a system integration concept, where individual technical solutions will be combined to one specific innovation. The use of various sensors and information tools for different and multiple applications within a vehicle is highly appreciated and will lead to synergies with reduced costs for the individual components. This philosophy will also be applied for lighting systems in the future. The potential applications and possible solutions will be described within this paper.
2002-07-09
Technical Paper
2002-01-1990
Michael Hamm
Adaptive Lighting systems generate different lighting patterns according to the environmental situation that is evaluated by electronic control units. On one side, the photometrical performance will be shown in measurements, e.g. photometric data and visibility/detection distances, reaction distances and braking distance calculation. A second approach will be the evaluation how the improved light performance is accepted by the driver when driving adaptive lighting systems. It can be assumed that the fact that during night time driving the fixation is mostly oriented in front of the car in illuminated areas, the visible change of light performance will lead to clear statements about acceptance among drivers. For this reason, a questionnaire is currently evaluated in order to find an acceptance rating for the different driving situations. The paper will address both fields of interest and describe the results in terms of traffic safety and comfort acceptance.
2002-07-09
Technical Paper
2002-01-1985
M. Brughmans, S. Goossens, V. Cibrario
Design of a vehicle system involves satisfying competing objectives for various attributes Noise and Vibration (NVH), Durability, Safety, and Vehicle Dynamics. To achieve an optimal design, dedicated CAE analysis tools are used to evaluate the functional vehicle performances for the different attributes and to quantify trade-offs when analyzing different design variants. Presently, CAE tools have been playing a reactive role in this engineering process. Different design proposals (CAD) are verified against functional requirements and feedback is given to the design department for the next design iteration. This paper aims at describing an engineering process where CAE (simulation) plays a more proactive role in the design process.
2002-07-09
Technical Paper
2002-01-1986
C. Mattheck, I. Tesari
Based on the axiom of uniform stress, which is a basic design rule for biological load carriers, and by use of the Finite Element Method (FEM) the computer program CAO (Computer Aided Optimisation) has been developed at Forschungszentrum Karlsruhe to transfer this biological optimisation mechanism to mechanical engineering. CAO leads to an optimised shape with a high fatigue resistance due to homogeneous stresses on the surface of the component. The conventional CAO method has been modified for the optimisation of shell structures. One modification of the CAO method allows a variation of the wall thickness of shell or membrane elements. Another modification is for the optimised corrugation of sheets of uniform thickness. The methods can be combined and are very useful for the reduction of the maximum stress or the minimization of the weight of load bearing sheets.
2002-07-09
Technical Paper
2002-01-1996
Bret D. Cannon, Chester Shepard, Mohammad Khaleel
We developed a non-destructive and non-contact method for measuring stress at the mid-plane of tempered glass plates that uses Bragg scattering from a pair of thermal gratings. These gratings are formed by 1064 nm beams from a seeded Nd:YAG laser and we measure the polarization state of light from a 532 nm beam that scatters from both these thermal gratings. The change in polarization of the doubly scattered light with separation between the two gratings allows measurement of the in-plane stress. Stress measurements are reported.
2002-07-09
Technical Paper
2002-01-1997
Xavier Muyldermans, Jean-Michel Mace
There is a definite trend toward the increasing use of “Glass Encapsulation Technology” in the automotive industry. In this technology a glass object such as a window is placed within a mould and an elastomer is injected around the window giving a tight sealing system. A wide variety of materials are currently used as the sealing materials in either static or semi-static encapsulated glazing systems, including a wide range of “elastomers”. New thermoplastic elastomer compounds are being developed that are characterized by their consistent properties; including high melt-fluidity, very good surface appearance, sealing properties, and resistance to weathering. Compound performance is highly dependent on formulation variables as well as the chemistries of the base materials. KRATON® SEBS polymers1 are block copolymers of styrene and ethylene/butylene.
2002-07-09
Technical Paper
2002-01-1998
André Galtier, Jean-Noel Gacel
Weight reduction and economy in the use of materials are the most important aim of automotive industries. Steel manufacturers develop high strength steel in order to increase mechanical properties. Fatigue behavior of assemblies is an important issue to consider, and in the case of thin steel sheet spot welding is the widely technique used. Is this paper, other techniques have been studied such as clinching and riveting. Fatigue tests were performed on different steel grades and several sheet thickness on a single spot specimen subjected to shear-tension loading. Results show that the fatigue strength of these assemblies is strongly dependant of the steel grade on the contrary of spot welds. Some tests on two spots specimens confirm that the fatigue strength is proportional to the number of spots. Then relationships in order to predict the fatigue strength from plate thickness are proposed from experimental results.
2002-07-09
Technical Paper
2002-01-2000
Yoshimasa Ureshino, Osamu Nakano, Kohichi Fukuda, Terumoto Fujiwara
Gas carburizing is a surface hardening method that is used for automobile steel parts such as gears. The conventional gas carburizing(at 1223K) takes longer time. Shortening the carburizing time will contribute greatly to the energy saving and CO2 reduction of parts production. The new carburizing process at higher temperature,1273K, and vacuum is made without adding reheating and quenching process. That process can shorten treatment time to one-fourth of conventional process. The new alloy steel for high-temperature vacuum carburizing is developed in order to prevent the grain coarsening. This paper describes the outline of this alloy steel.
2002-07-09
Technical Paper
2002-01-1992
M.K. El-Adawi, S. A. Shalaby, G. M. Behery
Abstract The daily temperature variation of the car's glass windows, supported with a metallic mesh being embedded in it and subjected to incident global solar radiation is obtained. A heat balance equation with terms considering heat losses by convection and thermal radiation is solved. A heat diffusion equation for the car's salon is also solved using Fourier sine transform technique. The effect of the mesh parameters and other main features on the salon climate are clarified through the obtained relations.
2002-07-09
Technical Paper
2002-01-1991
David A. Danaher, Wendy S. Johnson, Ben T. Railsback, Richard M. Ziernicki
Current windshield manufacturing processes produce residual tensile stresses near the edges of windshields. This residual tensile stress reduces the ability of the windshield to withstand suddenly applied external loading over a short time interval near the edge. Present manufacturing processes can reduce some of the residual tensile stress produced during the annealing process, but currently it is technically difficult to eliminate. However, an innovative and more cost-effective solution for the residual tensile stress problem has been proposed. Application of a thin film of polycarbonate around the perimeter of the windshield allows the energy generated during impact loading to be dissipated without the need to change the windshield's material properties.
2002-07-09
Technical Paper
2002-01-1993
Robert A. Esposito, Glenn E. Freeman
As noise levels within vehicle cabins continue to be reduced, wind noise and traffic noise transmitted through the glazing increase in importance in the quest to achieve further reduction. With consumers ranking cabin noise as an important factor in vehicle purchase decisions, and with the projected increase in vehicle telematics, including speech recognition systems, the need for even quieter interiors will continue. NVH engineers have not recognized that vehicle glazing offers an effective option for noise reduction; often, only monolithic glass has been considered, where the only option for improvement has been to increase the mass (increasing the thickness and the vehicle weight). This paper presents sound pressure loss data for laminated glass compared to the tempered glass typically used for side, rear and roof glazing today.
2002-07-09
Technical Paper
2002-01-1994
Jun Lu
Polyvinyl butyral (PVB) is used in laminated side glass on a number of automobiles. Protection against intrusion and vandalism and reduction of interior noise are two of the major benefits of PVB laminated side glass. While standard laminated glass performs to today's specifications, testing reveals new interlayer formulations of plasticized PVB, i.e., PVB/PET/PVB composite interlayer, have resulted in laminated side glass that shows enhanced intrusion resistance performance and maintains sound insulation property of standard laminated glass. The PVB layers perform their traditional task of intrusion prevention and noise reduction, while the PET layer provides stiffness to prevent collapse or pullout. Because of its multilayer composite structure, new performance features such as improved solar protection can also be added by modifying the composite interlayer structure.
2002-07-09
Technical Paper
2002-01-2047
A. Kanarachos, D. Koulocheris, V. Dertimanis, H. Vrazopoulos
The system identification procedure is a powerful and flexible tool for the modeling of dynamic systems. This paper implements the theory of parametric identification in order to estimate a valid model of a flexible robotic arm. For this purpose experimental data is used for the estimation of ARMAX SISO models. A two-stages identification procedure (non-parametric & parametric) provides an insight about the system under identification. In the first stage, known signal analysis methods are applied (correlation-spectral analysis) for the estimation of frequencies and frequency response, and in the second stage, the estimation of ARMAX models is performed in order to fit a transfer function model to collected input-output data set. For the estimation of model's coefficients, use of Evolutionary Algorithms is implemented.
2002-07-09
Technical Paper
2002-01-2127
Nobuyoshi Sasaki, William L. Tordoff, Kazuyuki Kurisu, Yuji Yoshida
This paper describes a newly developed high production, commercial, and economical metal casting process for steel and alloyed steel, capable of producing thin wall casting section sizes of 2-3mm. The Convert Mold Process was developed to meet the needs of automotive engineers and designers assigned the responsibility of reducing weight and using alternative materials that can withstand higher exhaust operating temperatures for the internal combustion engine. The process provides an opportunity to combine engine components through the utilization of a flexible casting process for steel and it's alloys. Typical applications of these thin wall, steel and alloyed steel components include: exhaust manifolds, catalytic converter canisters, manifold/converter combinations and manifold/turbo combinations.
2002-07-09
Technical Paper
2002-01-2045
Gu Zhengqi, Wu Jun
An advanced panel method is presented for simulating the airflow of arbitrary three-dimensional automotive body in the paper. The theory is about a wake synthesizer for panel methods that use an iterative procedure to determine the position of strongly interacting vortex sheets. The estimation of the wake geometry is based on blunt body theory with separation flow. The method is applied to the A-pillar separation on foreside of an automobile and be fit for determine the starting point for a three-dimensional iterative solution. Comparison with experimental data shows that calculations results with the estimated wakes are more reality than with the attached flow
2002-07-09
Technical Paper
2002-01-2135
Mahmoud Y. Demeri
Residual stresses in metals are caused by a number of processes such as inhomogeneous deformation, phase changes and temperature gradients. This investigation focuses on the residual stresses caused by plastic deformation of automotive metals. Such stresses are responsible for part springback and shape distortion in many manufacturing and assembly processes. Tensile residual stresses may lead to stress cracking and, in some alloys, to stress corrosion cracking which may ultimately lead to premature product failure. The residual stress potential of metals can be evaluated by using the Split Ring Test Method. The test can be used to evaluate the effect of materials on residual stresses in cup drawing. Drawn cups are used because they produce large amounts of residual stresses and, therefore, increase measurement accuracy and reduce experimental error. A closed form analytical solution is used to estimate residual stresses in split rings taken from sections cut from the drawn cups.
2002-07-09
Technical Paper
2002-01-2049
Christophe Cazes, François Ronin
The drive for improved safety and reduced fuel consumption has been changing drastically the requirement of materials in car structures and body. To follow these demands, steel manufacturers have designed and industrialized new high technology steels with different objectives: For closures, BH steels are now widely used and new qualities such as DP steels or sandwich steels will allow mass reduction up to 40% while keeping equivalent part properties For energy absorption relevant parts, while the requirements are being severed, use of new steels such as rephosphorized and dual phase allow already mass reduction of over 20% as compared as 10 years ago. New industrialized TRIP steels will allow carmaker to reduce further their parts weight. Anti intrusion parts benefit from combined new steel/processing technologies -such as roll forming of very high yield steels or hot forming of boron steels- to reach over 60% weight reduction compared to the situation in 1990.
2002-07-09
Technical Paper
2002-01-2048
L. Vaissiere, J. P. Laurent, A. Reinhardt
The automotive industry have to face with its will to increase the safety of the passengers and the necessity to reduce the pollutant emissions. Besides, the customers expect more and more high vehicle quality and especially as far as corrosion is concerned. The development of the pre-coated boron steel associated with the hot stamping allows PSA Peugeot Citroën and RENAULT to lighten their parts significantly and fulfill the automotive corrosion requirements. The benefit in crash resistance has been obtained by the increase of the mechanical properties after heat treatment. After a complete austenitisation in a 930°C furnace, the blanks are stamped and quenched in one step in a water cooled tool. This process allows to obtain: YS > 950 MPa TS > 1300 MPa.
2002-07-09
Technical Paper
2002-01-2051
Gwenael Plassart, Guylaine Philip
In order to lighten the body in white with respect to safety and comfort requirements, innovative material solutions have to be developed. In this field, PSA PEUGEOT CITROËN has defined a selection and certification policy in relation to main stages of vehicle development schedule. Then each step of the material certification has to be connected to main vehicle project milestones as follows : exploratory stage has to be completed before the concept choice, product and process feasibility before the numerical calculations, industrial certification before the final drawings. This strategy drives PSA PEUGEOT CITROËN to the use of different levels of high strength steels and aluminium for the body in white.
Viewing 1 to 30 of 244

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