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A study on light weighted injection molding technology and warpage reduction for lightweight automotive head lamp parts  

Jeong, Eui-Chul (Molds and Dies Technology Group, Korea Institute of Industrial Technology)
Son, Jung-Eon (Molds and Dies Technology Group, Korea Institute of Industrial Technology)
Min, Sung-Ki (CHANGDAE Precision Company)
Kim, Jong-Heon (CHANGDAE Precision Company)
Lee, Sung-Hee (Molds and Dies Technology Group, Korea Institute of Industrial Technology)
Publication Information
Design & Manufacturing / v.13, no.2, 2019 , pp. 1-5 More about this Journal
Abstract
In this study, micro cellular injection molding of automobile head lamp housing with uneven thickness structure was performed to obtain improvement on deformation and light-weight of the part. The thickness of the presented model was uniformly modified to control the deformation of the molded part. In order to maximize the lightweight ratio, the model having an average thickness of 2.0 mm were thinly molded to an average thickness of 1.6 mm. GFM(Gas Free Molding) and CBM(Core Back Molding) technology were applied to improve the problems of the conventional foam molding method. Equal Heat & Cool system was also applied by 3D cooling core and individual flow control system. Warpage of the molded parts with even cooling was minimized. To improve the mechanical properties of foamed products, complex resin containing nano-filler was used and variation of mechanical properties was evaluated. It was shown that the weight reduction ratio of products with light-weighted injection molding was 8.9 % and the deformation of the products was improved from the maximum of 3.6 mm to 2.0 mm by applying Equal Heat & Cool mold cooling system. Also the mechanical strength reduction of foamed product was less than 12% at maximum.
Keywords
Lightweight head lamp housing; Micro cellular injection molding; Core back molding; Equal heat & cool; Gas free molding; Individual flow control; Warpage reduction;
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