導電性複合材料於射出成型之EMI屏蔽效應研究

The Study of conductive polymer composite material by injection molding for preventing electromagnetic interference（EMI）

彭秉峰(Ping-Feng Peng)

指導教授 ： 陳夏宗

中原大學/工學院/機械工程研究所/碩士(2002年)

https://doi.org/10.6840/cycu200200501

摘要

摘 要
EMI（Electromagnetic Interference, EMI）是3C產品（Computer, Communication, Consumer Electronics）重要的功能指標也是塑膠零件相較於金屬零件在應用時較為劣勢之處，因此本文探討導電性複合材料於射出成型之防電磁波干擾（Electromagnetic Interference, EMI）屏蔽效應。主要針對添加4mm長之不鏽鋼纖維（Stainless Steel Fiber, SSF）於透明ABS塑膠基材後進行射出成型，探討其成型製程條件對於防EMI屏蔽效果的影響。並針對纖維在流動中其分佈性及排向性對於防EMI影響作微觀組織的觀察，以光學顯微鏡（Optical Microscope, OM）作其金相分析，此外亦配合影像程式計算不同製程條件之試片對於防EMI之關係。
研究中使用標準圓盤試片依照ASTM D4935-89標準試驗方式對其進行防EMI性質測試，結果發現放慢射速可減低纖維被打斷及纖維糾結的情況發生，對於其防EMI屏蔽值（Shielding Effectiveness, SE）有較佳的效果；而料溫的提高則有助於導電性纖維在分散性上達到更好的效果，而使其防EMI性質相對地提昇；提高模溫則有助於流動性良好使得纖維在流動中能更均勻的分佈，所以與料溫有相同的提昇效果。此外觀察纖維分佈情形並配合影像程式分析之結果，纖維的分散性佳及分佈面積平均對於防EMI性質有著較佳效果之關係。

關鍵字

導電性複合材料 ； EMI屏蔽效應 ； 射出成型

並列摘要

Abstract
This research investigates the effect of conductive polymer composite material by injection molding for preventing electromagnetic interference（EMI）.The effects with different injection molding parameters upon the shielding effectives（SE） of 4mm stainless steel fiber（SSF） adding in ABS plastic matrix were investigated. The microstructure observed by scanning optical microscope（OM）show the SSF dispersion and orientation to the inference of EMI shielding effectiveness. Then using VB image program to find the relation of different process parameter of injection molding for EMI.
In this study, the test disk and its mold were designed by standard EMI test based on ASTM D4935-89 test method. The results show that low injection velocity can reduce the chance of the breaking fiber and the fiber banding together. As regards have the effect to increase the shielding effectiveness（SE）values .High melt temperature can obtain the effect of good fiber dispersion and increase the shielding effectiveness（SE）values. High mold temperature can obtain the effect of good fiber distribution and increase the shielding effectiveness（SE）values. Besides, the fiber distribution and dispersion were observed by optical microscope（OM）and VB image programming. As the result, good fiber dispersion and distribution have the relation of the shielding effectiveness（SE）values could be as an assistant proof.

並列關鍵字

electromagnetic interference（EMI） ； conductive polymer composite material

參考文獻

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