本論文探討FPC(Flexible Print Circuit)連接器表面氣泡之形成原因與研究其解決方案。FPC連接器經高溫迴焊爐與硬式電路板焊接後,在連接器表面偶而產生氣泡,造成 1.667 %的不良率。本研究運用田口實驗設計法研究氣泡形成原因與解決方案,根據參考文獻與指導教授的建議決定實驗因子及最佳化成型條件。本論文運用電腦輔助工程(CAE)模流分析軟體(Moldflow)分析FPC連接器在射出成形過程中成型條件對氣泡形成的影響;研究結果發現射出速度、熔膠溫度、模具溫度、保壓壓力等四項成型條件是造成起泡的主要因素,其中前三項與剪切率直接相關。實驗證明高剪切率為連接器表面氣泡之形成原因,降低剪切率可降低連接器表面氣泡形成機率。另優化原始成型條件,將射出速度降低、熔膠溫度降低、模具溫度不變、保壓壓力提高,可降低5.67×104 s-1的剪切率與1.667 %的不良率。
This research is talking about the reason and solution of FPC (Flexible Print Circuit) connector’s surface blisters at a defect rate of 1.667%. These blisters occasionally can be found after the connector passes through IR reflow soldering, when soldering between PCB (Printed Circuit Board) and FPC connector. The experiment will be based on the Taguchi method and according to previews literatures and the advising professor’s suggestions it was decided the factors of the experiment to research the reason and solution of the blisters. CAE software-Moldflow is going to be used to find out the effect between the molding condition of FPC connector and the blisters. According to the result of the experiment, the ram speed, melt temperature, mold temperature, and packing pressure are major factors that lead the blisters to appear, being the first three factors directly related to the shear rate. Usually, if the shear rate is too high, the rate of material degrading and generating some gas will be higher. Therefore, we got an optimal condition by lowering the ram speed and the melt temperature, keeping the mold temperature as the same, and increasing the packing pressure, will reduce the 5.67×104 s-1 shear rate and 1.667% defect rate to a lower rate.