• Proceedings of the KSME Conference
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• 2001.06a
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• pp.692-697
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• 2001

It is necessary to analyze the mechanical behaviors of the power steering hose, which must play a proper role under severe operating conditions, in order to prepare a preventive measure fur contrary effects expected in unfavorable circumstances. In this paper, the stress and deformation characteristics of the hose components such as rubber, sleeve, nipple and reinforced braids during the swaging process, are analyzed using the finite element method. Contact conditions identical to the manufacturing process are taken into account, and the material properties based on experimental data are used in the analysis. Investigations into the mutual relations between the manufacturing conditions and the hose performances are done with respect to the jaw stroke on the basis of the stress and strain values of the hose components after swaging process.

• Journal of the Semiconductor & Display Technology
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• v.11 no.2
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• pp.39-43
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• 2012

This paper presents a study on the design of a pulling module for silicon ingot and an apparatus of manufacturing silicon single crystal ingot using the same method. The pulling module is conceptually designed by using TRIZ. Czochralski method(CZ) is representative way to manufacture single crystal ingot for wafers. The seed can be broken by high tension which is caused by large weight of a silicon ingot. The solution of this problem has been derived using 6SC(6 steps creativity)TRIZ. The pulling module is actuated by DC motor and rollers. High tension in the seed is removed by the rotate-elevate motion of rollers in the pulling module. A rubber belt is included in the rotate-elevate mechanism for increasing friction between rollers and silicon ingot.

• Elastomers and Composites
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• v.57 no.2
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• pp.48-54
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• 2022

A polymeric adhesion promoter was synthesized to improve the adhesive strength of the Ni lead frame/epoxy composite. Poly(itaconic acid-co-acrylamide) (IAcAAM) was prepared by copolymerizing itaconic acid and acrylamide. We compared the adhesive strength between the Ni lead frame and epoxy composite according to the molecular weight of IAcAAM. The molecular weight of IAcAAM was controlled using an initiator, which made it possible to use IAcAAM in the epoxy molding compound (EMC) manufacturing process by modulating the melting temperature. The adhesive strength of Ni lead frame/epoxy composite increased with the addition of IAcAAM to the epoxy composite. In addition, as the molecular weight of IAcAAM increased, the adhesive strength of the Ni lead frame/epoxy composite slightly increased. We confirmed that IAcAAM with an appropriate molecular weight can be used in the EMC manufacturing process and increase the adhesive strength of the Ni lead frame/epoxy composite.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.2
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• pp.206-212
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• 2014

Liquid silicone rubber (LSR) has been widely used in automotive, electrical, and medical components. Thus, research on the use of LSR in the injection molding process is required to obtain high-quality and high-performance products. In this study, a mold was fabricated to examine the effects of the process parameters on the molding and mechanical properties of LSR parts. A computer-aided engineering analysis was used to optimize the air vent depth and curing temperature to decrease the flash at the air vents caused by the low viscosity of LSR. Temperature and pressure sensors were mounted in the mold to determine the effects of the process parameters on the temperature and pressure in the cavity. The tensile strength of the LSR parts was also examined in relation to the process parameters.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.8
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• pp.79-86
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• 2022

With the recent increase in the demand for electric vehicles, it is necessary to identify the high current safety of automobile parts. Among the automobile parts, the EPDM parts required colored parts from the existing black; therefore, it was necessary to change the basic filler from carbon black to silica. The rubber used in automobile parts is flexible and exhibits basic characteristics of high strength and elongation. However, as the filler is changed to silica, its physical properties, such as tensile strength and elongation, are lower than those of the existing carbon black base. Therefore, it is necessary to evaluate the mechanical properties with the addition of the EPDM compound using silica as a base without degrading the physical properties of EPDM. In this study, an experiment based on the additive content was performed using the mixture experimental planning method to analyze the mechanical properties according to the additive type and mixing ratio of silica-based EPDM. The mixing ratio of the four additives was set using a simplex lattice design, and the tensile strength, elongation, modulus 300%, and permanent compression reduction rate were analyzed for mechanical characteristics, and rheometer experiments were performed for vulcanization characteristics. Through statistical analysis of the measured data, the main effects and interactions of the EPDM-blended rubber additives were analyzed. These results can be used to derive a mixing ratio of additives that satisfies the required characteristics of the EPDM compound.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.3
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• pp.39-46
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• 2011

The automotive air conditioning hose is used for connecting the components of air conditioner in a vehicle. The hose is usually manufactured by the swaging process to connect the rubber hose with the metal fitting at the end of the hose. In case that the clamping force is small, the refrigerant gas in the hose can leak locally under the severe operating circumstances. The practical test of clamping force is performed by means of the measurement of separation force. In this study, the swaging process of a hose is simulated with the finite element method, to investigate the effect of friction coefficient on the clamping force. The contact condition is used in consideration of real manufacturing process, and the material properties for the Mooney-Rivlin model is obtained by the experimental results. The result interpretations are focused on the contact forces, which is displayed graphically with respect to friction coefficient, on the surfaces between the hose and the metal fittings.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.5
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• pp.1-8
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• 2013

Roll-based, nanoimprint lithography (Roll-NIL) is one effective method to produce large-area nanopatterns continuously. Systems and processes for Roll-NIL have been developed and studied for more than 15 years. Since the shapes of the stamp and the substrate for Roll-NIL can be plates, films, and rolls, there exist many concepts to design and implement roll-NIL systems. Combinations and variations of contact-methods for variously shaped stamps and substrates are analyzed in this paper. The contact-area can be changed by using soft materials such as polydimethylsiloxane (PDMS) or silicone rubber. Ultraviolet (UV) sources appropriate for the roll-to-plate or roll-to-roll process are introduced. Finally, two roll-to-plate nanoimprint lithography systems are illustrated.

• Elastomers and Composites
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• v.44 no.4
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• pp.378-383
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• 2009

In this study, the use of a condensed model is proposed for the simulation of forming of sandwich sheet with pyramid core. A corresponding finite element analysis for L-type bending is carried out to prove the accuracy and the effectiveness. In order to improve the accuracy of forming analysis, more precise modeling of core shape and consideration of work-hardening of previous core forming are carried out. Simulation results are compared with those of experiment. Deformation shape and post-buckling behavior by simulation are in good agreement with those of experiment for the considerable range of deformation. From the comparison of force-displacement curve, it is shown that the proposed model shows good prediction of post-buckling behavior.

• Elastomers and Composites
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• v.51 no.4
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• pp.275-279
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• 2016

Additive manufacturing or 3D printing is a new manufacturing process and its application is getting growth. However, the product qualities such as mechanical strength, dimensional accuracy, and surface quality are low compared with conventional manufacturing process such as molding and machining. In this study not only mechanical characteristics of polymer sandwich panel having three dimensional core layer but also mechanical characteristics of core layer itself were analyzed. The shape of three dimensional core layer was pyramidal kagome structure. This core layer was fabricated by two different methods, injection molding with PP resin and material jetting type 3D printing with acrylic photo curable resin. The material for face sheets in the polymer sandwich panel was PP. Maximum load, stiffness, and elongation at break were examined for core layers fabricated by two different methods and also assembled polymer sandwich panels. 3D printed core showed brittle behavior, but the brittleness decreased in polymer sandwich panel containing 3D printed core. The availability of 3D printed article for the three dimensional core layer of polymer sandwich panel was verified.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.1
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• pp.74-85
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• 2010

In order to formulate the compounded polypropylene(C-PP) which is suitable to an automotive door trim panel, 9 sorts of properties were measured after manufacturing the C-PP using an extruder and an injection machine with polypropylene(PP), ethylene-octene rubber(EOR) and talc. Mixture design, especially extreme vertices design, in DOE with MINITAB - commercial software was used to analyze the data. The relations between each property and each component, for example, $y=0.00907222x_1+0.00870556x_2+0.0155722x_3$ for specific gravity, were found out by the regression analysis and the variance analysis. The optimized formulation of the C-PP for an automotive door trim panel was acquired at PP(77.6962), EOR(11.0238) and talc(10.2800) by use of the response optimizer(mixture) in MINITAB.