• International Journal of Automotive Technology
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• 제6권3호
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• pp.277-283
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• 2005

Formability simulation of automotive panels at early design phases can reduce product and tooling development time and cost. However, for the simulation to be effective in leading the design process, fast and reliable results should be achieved with limited design definition and minimum modeling effort. In this paper, nonlinear finite element analysis is used to develop an automated process for the formability simulation of automotive body panels at early design phases. Due to the limited design definition at early design phases, the automated simulation process is based on the plane strain analysis for selected number of typical sections along the panel. Therefore, an entire panel can be analyzed with few sections. The state of plane strain can be easily induced, during simulation through symmetry and applied boundary conditions that simplify the modeling process. To study the reliability and effectiveness of the developed simulation process, the analytical results are compared with measured results of production automotive body side panels. The comparison demonstrates that the developed simulation process is reliable and can be effective for analyzing sheet metal formability, in early vehicle development phases.

• 한국자동차공학회논문집
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• 제6권4호
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• pp.32-38
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• 1998

In order to investigate the relationship between the stiffness and structure of the automotive roof panels, two kinds of glass fiber reinforced plastic(GFRP) roof panels without and with insert material were fabricated by resin transfer molding(RTM) method. The stiffness test was performed at the same condition as it of actual driving. The structural design and material selection for improving the recyclability of GFRP roof panels were also covered.

• Corrosion Science and Technology
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• 제2권5호
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• pp.247-251
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• 2003

The corrosion forms of automotive body panels are various. One of the representations is a corrosion pitting and its propagation on the lapped portion by galvanic corrosion. But it has been difficult in correlation analysis about the corrosion propagation rate and mechanism of pitting and the actual automotive body in field. This present study interprets experimentally the rust pitting occurrence mechanism on the lapped panels through experimental methods. And field car investigation was executed for correlation analysis with experimental results. This paper compares corrosion propagation rate by pitting on hot-dip galvannealed steel sheets with corrosion forms in the automotive field condition. The research fundamentals which make it possible to predict the pitting occurrence and propagation on the lapped panels in the actual vehicles are given.

• 한국자동차공학회논문집
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• 제4권6호
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• pp.27-38
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• 1996

A two-dimensional FEM program, which considers bending effects in the membrane fromulation, was developed under plane strain assumption for analyzing forming processes of an arbitrarily shaped draw-die of automotive panels. For the evaluation of bending effects with membrane elements, the bending equivalent forces and stiffnesses are calculated from the bending moment computed using the changes in curvature of the formed shape of two membrane ones. The curves depicted with 3 nodes are described by a circle, a quadratic equation, and a cubic equation, respectively, and in the simulation of the stretch/draw sections of an automotive inner panel, three different description results are compared each other. Also, the bending results are compared with membrane results and measurements in order to verify the validity of the developed program.

• 소성∙가공
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• 제26권1호
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• pp.55-62
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• 2017

This paper proposes the process to develop a light-weighting automotive door assembly using high strength steel with low cost penalty. In recent years, the automotive industry is making an effort to reduce the vehicle weight. In this study, inner panels for automotive front door using thinner sheets and quenchable boron steel were designed to reduce the weight of conventional one. In order to evaluate the stiffness properties for the proposed door design, the several static tests were conducted using the finite element method. Based on the simulation results, geometry modifications of the inner panels were taken into account in terms of thickness changes and cost saving. Furthermore, a prototype based on the proposed design has been made, and then static stiffness test carried out. From the results, the proposed door is proved compatible and weight reduction of 11.8% was achieved. It could be a reference process for automotive industry to develop the similar products.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2002년도 춘계학술대회 논문집
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• pp.103-107
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• 2002

The 2nd forming process of flanging/hemming has recently many interest because it determines external quality of automobile. It is difficult to apply finite element simulation in flanging/hemming due to small element size which needs for expression of bending effect on the die corner and big model size of side door, back door, tank lid and like opening Parts. This paper shows the process of flanging/hemming simulation using finite element model for automotive panels. The explicit finite element program PAM-STAMP$\^$TM/ was used to simulate the flanging and hemming operations.

• 한국표면공학회지
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• 제25권2호
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• pp.57-65
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• 1992

Increasing demands of high corrosion resistant sheet steels for the automotive body panels have been leading to a tendency toward heavier coatings of electroplated sheet steels. The specimens were prepared from lab-scale electroplating simulator with various coating weights of zinc, zinc-iron and zinc-nickel coated sheet steels and evaluated in the light of the application for the automotive body panels. Corrosion resistances by sacrificial action were improved with increasing coating weights for all electroplated sheet under survey, but blistering resistances of pure zinc coated sheet steels were not as much. On the other hand, the adhesions of heavy alloy coatings showed poor powdering performances by the external compressive or tensile forces.

• 소성∙가공
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• 제13권2호
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• pp.115-121
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• 2004

Hemming is the last farming process in stamping and determines external quality of automotive outer panels. Few numerical approaches using 3-dimensional finite element model have been applied to a hemming process due to small element size which is needed to express the bending behavior of the sheet around small die comer and comparatively big model size of automotive opening parts, such as side door, back door and trunk lid etc In this study, part model assembling method is suggested and applied to the 3-dimensional finite element simulation of flanging and hemming process far an automotive front hood.

• 오토저널
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• 제14권4호
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• pp.68-78
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• 1992

Vibration and vibro-acoustic characteristics of body panels enclosing the vehicle interior cabin are tested and analyzed for effective application of sound proofing materials. A set of deadener and insulation packages are proposed based on the experimentally evaluated and categorized contributions of noise radiating panels. The suggested packages are applied to a prototype vehicle, and a refined acoustic quality is achieved. A systematic experimental procedure proposed in this study can be a good tool in tuning the acoustic quality of prototype vehicles within a limited development period.

• 한국생산제조학회지
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• 제22권6호
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• pp.1018-1024
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• 2013

In the process of draw die design for stamping automotive press panels, the addendum surfaces generated in metal forming simulation software cannot be used in downstream processes such as machining and making draw dies because simulation tools use simple discrete models for the surface geometry. The downstream processes require more precise and continuous geometric models such as NURBS surfaces. Generally, automotive die engineers manually regenerate the addendum surface geometry using the discrete model. This paper presents an automated geometric modeling process for generating addendum surfaces using draft surface models. The design parameters of the section curve for the addendum surfaces are extracted automatically from the draft geometry. Using the extracted design parameters, smooth addendum surfaces are generated automatically as NURBS surfaces. The generated surfaces are $G^1$ continuous with the part surface and the binder surface, and can be used in downstream processes.