使用背撐機構以減少複合材料圓管鑽孔脫層之探討

Applying Back-up Mechanism to Reduce Delamaination in Drilling Composite tube

蘇郁仁(Su, Yu Ren)

指導教授 ： 賀陳弘 ； 曹中丞

國立清華大學/工學院/動力機械工程學系/碩士(2016年)

摘要

複合材料因其優異的機械性質而被廣泛運用於各個領域中，如航太業、汽車工業、運動器材等，當複合材料需要進行鑽孔作為元件連接之用時，其加工過程所產生的脫層現象，除了對加工品質有影響外，對複合材料構件的機械性能與壽命也會有所影響，因此如何減少脫層現象成為複合材料鑽孔加工的主要課題。本文介紹的是一種改善複合材料圓管鑽孔脫層的方法。
　　鑽孔平板複合材料時，可在平板下方放置一塊墊塊，稱做背板(Back-up)，來減少複合材料的脫層現象，本文以此為出發點，設計了用於鑽孔圓管複合材料的背撐機構，在圓棒中間放置一弧面頂塊作為支撐，來減少鑽孔時產生的脫層，並提升背撐機構的剛性，期望能減少更多的脫層現象。本實驗試片使用碳纖維管，使用麻花鑽頭進行鑽孔加工，透過使用背撐機構，以及多組進給速率、主軸轉速為變數，得到的實驗結果顯示，使用原先的背撐機構，能在提升兩倍的轉速以及三倍以上的進給速率下，得到與不使用背撐機構的脫層面積相同的結果，提升剛性之後，更可達到減少35％脫層的改善效果，具更好的加工效益。

關鍵字

脫層 ； 鑽孔 ； 複合材料 ； 背撐

並列摘要

Composite materials have been widely used in aerospace, electrical vehicles and sports goods. The delamination occurs when drilling the composite materials parts for assembly, which leads to serious concerns of reliability and safety. How to reduce delamination is a major issue in drilling composites. This research presents a method of utilizing back-up mechanism which places a supporting block mades of carbon steel in the middle of the tube to reduce the delaminations caused by twist drilling. Increasing stiffness of back-up mechanism can also reduce delamination. The experimental results demonstrate that drilling feed rate can be elevated 300% and spindle rotating speed can be elevated to 200% when maintaining the same level of delamination extent. After Increasing stiffness of back-up mechanism, the delamination extent can be reduced up to 35%.

並列關鍵字

Composite material ； Drilling ； Delamination ； Back-up

參考文獻

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