ABS薄殼射出成型件縫合線之探討

Study on Weld-line of ABS Thin-wall Injection Molding Parts

鍾明修(Ming-Hsiu Chung)

指導教授 ： 陳夏宗

中原大學/工學院/機械工程研究所/碩士(2001年)

https://doi.org/10.6840/cycu200100337

摘要

中文摘要
當塑膠產品的發展越來越輕薄短小時，人們對其強度與品質的要求以及相關的影響因子也越來越重視，而「縫合線」即是其中一項主要的因子。為了探討縫合線對薄殼塑膠產品品質及強度的影響，本研究即以ABS工程塑膠為對象，針對其在薄殼成型時，不同厚度及不同製程條件下所產生的縫合線成品，進行符合ASTM標準的拉伸試驗與機械性質方面的比較研究。
本研究係利用迴歸分析法，參考Kim和Suh所建立的高分子縫合線鍵結強度理論模型，但考慮其為與厚度、料溫、模溫、保壓壓力、射出速度等製程參數有關，以更符合真正成型的狀況，因此而推導出一新的半經驗公式，可以與實際實驗的結果吻合；這是首次將縫合線理論用在ABS的薄殼產品上，也是預測、分析薄殼產品強度研究上的一項新的進展與貢獻。
本研究的結果並顯示，在製程參數對成品強度與健結度的影響程度上，與其他使用不同塑膠材料或較厚成品的研究比較，有大體相同的理論驅勢，但也有因本研究成品較薄及使用ABS所造成的差異，可以提供本領域業者在發展精密薄殼射出成型技術時，改善產品品質之參考。

關鍵字

自我擴散係數 ； 鍵結度 ； 抗拉強度 ； 縫合線

並列摘要

Abstract
The location and the strength of weld-line have become an important issues in injection molding industry, especially the plastic products are tend be light-weight and thin wall structures. To improve mechanical quality of products and predict the strength of weld-line, this study focuses on molding parameters, mechanical properties and degree of bonding for Acrylonitrile Butadiene Styrene Copolymer (ABS) material various thickness and manufacturing processing parameters. The tensile strength, which follows the ASTM standard in order to compare with the mechanical properties with different manufacturing processing parameters, of the ABS specimens were investigated.
According to theoretical polymer strength of weld-line model, proposed by Kim＆Suh, the semi-empirical equation, which includes the processing parameters, such as thickness, material temperature, mold temperature, packing pressure and injection velocity, is derived and compared with the experimental results. The primary results indicate that the semi-empirical equation can predict the mechanical properties at thin-wall injection molding product well.
Generally current study results are similar to other studies with different material. And the diversity can provide a general design methodology in product design to develop a thin-wall injection molding products in ABS material.

並列關鍵字

tensile strength ； degree of bonding ； self-diffusion coefficient ； weld-line

參考文獻

1.S. C. Malguarnera, “Weld Line in Ploymer Processing”, Polym. –Plast. Technol. Eng., pp. 1-45, Jan. (1982).

2.S. G. Kim and N. P. Suh, “Preformance Prediction of Weldine Structure in Amorphous Polymers”, Polym. Eng. and Sci., Vol. 26, No. 17, Sept. (1986).

9.J. Bozzelli, “Pressure Loss in Thin Wall Moldings” , SPE Tech. Paper, 173, 425, (1997).

10.Tantakom, “Processing Strattegies for Thin Wall Injection Molding”, SPE Tech. Paper, 367, (1998).

14.R. P. Wool and K. M. O’Connor, ”A Theory of Crack Healing in Polymers”, J. Appl. Phys., pp.5953-5963, (Oct. 1981).