反向開模的射出成型品之進膠痕跡的探討

Discussion of Gate-marks on Injection Molded Samples from Reverse Mold

黃冠擇(Guan-Tze Huangn)

指導教授 ： 鍾文仁

中原大學/工學院/機械工程研究所/碩士(2014年)

https://doi.org/10.6840/cycu201400049

摘要

觀察到反向開模的射出成型產品外觀表面有光澤不一致的缺陷，此缺陷在澆口對面部位約直徑1~2cm的範圍，看起来比四周還要稍微暗一些，此缺陷的位置在澆口對面處的外觀表面上，因而稱此缺陷為進膠痕跡。
透過彩色3D雷射共軛焦顯微鏡對產品表面的型態觀察、傅利葉紅外線光譜儀分析與氣相層析-質譜儀分析，探討產品表面的表面粗糙度、以及有無異物和材質變化；將分析資料進行整理與探討，並推論造成進膠痕跡的原因，歸納可能的改善方式後，進行射出實驗規劃，而後進行射出成型驗證，並觀察成型驗證的產品可否消除進膠痕跡。
發現缺陷處與四周的正常部位相比，多存在1~2μm程度的高低平面的差異，此高低平面的差異產生不定形凸起，是導致外觀表面光澤差異的原因。

關鍵字

射出成型 ； 光澤度 ； 表面粗糙度

並列摘要

A common defect to reversely positioned mold, which is a reflection difference like darker spot appearing at the area where ranges 1~2cm diameter against to the gate, is so called Gate-marks due to the location it is identified.
Color 3D laser scanning confocal microscope and Fourier transform infrared spectroscopy (FTIR) and gas chromatography - mass spectrometer (GC-MS) are utilized to scrutinize the possible cause from various aspects as product surface roughness, foreigner existence and material deviation. Further study plan is to be made as per the result of integration and analysis of above data, then followed with verification of practical injection to validate the possibility to eliminate the visible mark.
From the comparison of the defective and normal area, 1~2μm texture depth difference was discovered and considered the root cause to visible light reflection deviation.

並列關鍵字

Surface roughness ； Injection molding. ； Gloss

參考文獻

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