• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.159-165
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• 2002

So far, an alternator pulley has been formed by cold forging and casting with a metal due to the necessity of its high strength. Various advantages such as the light weight, the low cost, and the high productivity can be obtained by the injection molding process using engineering plastics. Engineering plastics have an excellent performance in the characteristics off strength vs. weight, a good forming ability and a productivity. The object of this study is to develop an alternator pulley, which has been made with a metal, using the injection molding process based on Taguchi methods. A sink mark is considered as a characteristic parameter to improve the quality. The FEM Simulation CAE tool, Moldflow, is used for the analysis of injection molding process.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.5
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• pp.30-37
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• 2002

Single flighted screw injection technology is the most cost effective method for the production of film, sheet, pipe and the fundamental step in other processes including blow molding and injection molding. The temperature of polymer melts and injection pressure play a very important role in the injection molding machine. Thermal distortion and displacement of a screw by temperature difference and injection pressure difference ratio cause a friction and thermoelastic wear by metal-to-metal contact between the screw and the cylinder. In this paper we analyzed thermal distortions of a screw as functions of temperature distribution and pressure profiles by finite element analysis.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.2
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• pp.87-92
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• 2015

The injection molding process is widely used in the production of most plastic products. In order to make metal-colored plastic products like those found in modern luxury home alliances, metallic pigments are mixed with a basic resin material for injection molding. However, process control for metal-colored plastic products is extremely difficult due to the non-uniform melt flow of the metallic resin pigments. In this study, the effect of process parameters on the quality of a metal-colored plastic product is evaluated. A rapid mold cooling method using a compressed cryogenic fluid is also proposed to decrease the content of undesired compounds within the plastic product.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.93-94
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• 2006

A novel production method for porous metal components has been developed by applying powder space holder (PSH) method to metal powder injection molding (MIM) process. The PSH-MIM method has an industrial competitive advantage that is capable of net-shape manufacturing the micro-sized porous metal products with complicated shapes and controlled porosity and pore size. In this study, the small impeller with homogeneous micro-porous structure was manufactured by the PSH-MIM method. The effects of combinations in size and fraction of PMMA particle on dimensional tolerance and variation of sintered porous specimens were investigated. It was concluded that the PSH-MIM method could manufacture commercially microporous metal components with high dimensional accuracy.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.833-836
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• 1997

Magnesium alloys are one of light weight material. Strength and stiffness of Magnesium alloys are enough to use for commercial product. Demand for strong, lightweight parts several computer and electronics have driven much of Magnesium injection molding's growth so far. And it is eighth most abundant resource on earth. In electronic device, electromagnetic interface and electrostatic discharge can affect performance. Magnesium injection molding is similar to normal plastic injection molding process. But some process condition is different. Especially injection speed and process temperature are so differs from other injection molding system. It just start for make something. But Magnesium injection molding is one of best alternate process for producing metal alloy part.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.43-44
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• 2006

The production method of micro sacrificial plastic mold insert metal injection molding, namely ${\mu}-SPiMIM$ process has been proposed to solve specific problems involving the miniaturization of MIM. Two types of sacrificial plastic molds (SP-mold) with fine structures were used: 1) PMMA resist, 2) PMMA mold injected into Ni-electroform, which is a typical LIGA (${\underline{L}}ithographie-{\underline{G}}alvanoformung-{\underline{A}}bformung$) process. Stainless steel 316L feedstock was injection-molded into the SP-molds with multi-pillar structures. This study focused on the effects of metal particle size and processing conditions on the shrinkage, transcription and surface roughness of sintered parts.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.212-220
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• 2000

Single flighted screw extrusion is the most cost effective method for the production of film, sheet, pipe and the fundamental step in other processes including blow molding and injection molding. The temperature of polymer melts and injection pressure play a very important role in the injection molding machine. Thermal distortion and displacement of screw by temperature difference and injection pressure difference cause adhesive wear by metal-to-metal contact. In this paper we analyze thermal distortion and stress of screw includes pressure and temperature distributions by finite element analysis to understand dynamic characteristics of screw.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.767-768
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• 2006

In this study, copper vapor chambers with built-in cooling fins, which eliminated the soldered or brazed joints in the conventional vapor chamber, were fabricated using the metal injection molding process. The results show that with optimized molding parameters, fins with an aspect ratio up to 18 could be produced. After sintering, the densities of the fin and chamber reached 96%. With only 32 cooling fins and a small fan installed, the thermal resistance of the heat sink was $1.156^{\circ}C/W$, and the power dissipation was 40W when the junction temperature was $70^{\circ}C$. When copper powder was sintered onto the chamber to make a vapor chamber, the thermal resistance decreased to $1.046^{\circ}C/W$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.42-47
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• 2017

In this study,we conducted an injection molding analysis of metal powder materials for the development of flanges, which are necessary adapters for optical communication. The metal powder injection molding process is a technique for producing an injection molded article having a complicated shape by mixing ceramic or stainless powder and binders. It is used to produce products which require complex processing technology or for which the productivity is low. The purpose of this study is to minimize the manufacturing processing of products which are manufactured through existing mechanical processing procedures. For the injection molding analysis, we mixed stainless STS316 metal powder with binders at a ratio of 6 to 4 to make molding materials consisting of granular pellets. Then, three-dimensional modeling and meshing were carried out to obtain the optimal injection molding analysis conditions(molding temperature, melting temperature, injection time, injection temperature, injection pressure, packing time and cooling time). As a result of the analysis, it was discovered that the inlet became available 13.29 seconds after the first injection. Also, as the flowing and packing in the melt through the sprue, runner and gate were stable, it is expected that good molds can be manufactured.

• Design & Manufacturing
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• v.16 no.3
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• pp.1-8
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• 2022

In this study, an artificial neural network(ANN) was constructed to establish the relationship between process condition prameters and the qualities of the injection-molded product in the injection molding process. Six process parmeters were set as input parameter for ANN: melt temperature, mold temperature, injection speed, packing pressure, packing time, and cooling time. As output parameters, the mass, nominal diameter, and height of the injection-molded product were set. Two learning structures were applied to the ANN. The single-task learning, in which all output parameters are learned in correlation with each other, and the multi-task learning structure in which each output parameters is individually learned according to the characteristics, were constructed. As a result of constructing an artificial neural network with two learning structures and evaluating the prediction performance, it was confirmed that the predicted value of the ANN to which the multi-task learning structure was applied had a low RMSE compared with the single-task learning structure. In addition, when comparing the quality specifications of injection molded products with the prediction values of the ANN, it was confirmed that the ANN of the multi-task learning structure satisfies the quality specifications for all of the mass, diameter, and height.