摘要: | 現實生活中共射成型技術是製造多材質產品之有效方法,然而,因為須同時整合許多設計與操作參數,特別是如何有效控制不同材料所構成之中間界面。另一方面,為能大量生產降低成本,許多產品生產牽涉到應用多模穴共射系統,但現階段此等系統內部之機理與操作,也仍未全然掌握有鑑於此,本研究鎖定非幾何對稱之多模穴共射系統,首先我們將探索在不同材料黏度效應組合時,皮層與芯層所構成之中間界面將如何變化。以低黏度A及高黏度B排列三種不同皮層/芯層組合:A/A系統、A/B系統及B/A系統。在A/A組合系統中,當我們固定皮層與芯層比例,以及固定充填流率時,改變其他操作條件幾乎都無法有效改變皮層與 芯層之中間界面之行為變化。在A/B組合系統中,對比於A/A系統,它形成較長且較窄之中間界面。在B/A組合系統中,反而形成較短且寬之中間界面。另外,在A/A組合系統中,當射出充填速度增加時,芯層之滲透距離將減少;此種中間界面滲透距離減少現象也同時可在A/B系統及B/A系統中觀察到。最後,實驗驗證結果顯示,實驗與數值分析預測相當吻合。 Co-injection molding, one of the multi-component molding methods, is commonly used in our daily life product. However, there are too many combinations of designs and parameters, how to properly control of co-injection is very challenge. Furthermore, co-injection with multi-cavity system is still not fully understood yet. In this study, we have focused on a nonsymmetrical multi-cavity system. First, we tried to find out how the viscosity difference effects on the variation of the interface between skin and core layers in co-injection molding. In A/A system, with a unique skin-to-core ratio and a fixed flow rate, general operation parameters have no significant effect on the change of the interface between skin and core. In A/B system, it generates longer and narrower locus than that of A/A system. On the other hand, in B/A system, it generates shorter and wider locus than that of A/A system. Moreover, in the presence of flow rate variation, as flow rate increased, the penetration distance of interface between the skin and core is reduced for A/A system. This reduction phenomenon on the penetration distance of the interface is also observed in A/B and B/A systems. Finally, the experimental study is also performed to verify the numerical predictions on the viscosity difference effects. Specifically, in the presence of flow rate variation, the numerical prediction on the interface between the skin and core is in a good agreement with the experimental data in trend. |