超塑性成形與快速塑性成形分析比較

Superplasticity Effect and Superplastic Forming vs. Quick Plastic Forming with AA5XXX Sheets

洪薪富(Xin-fu Hong)

指導教授 ： 李雄

國立中央大學/工學院/機械工程學系/碩士(2015年)

摘要

摘要
以低的氣壓進行金屬鈑片熱成形在工業界是具有它獨有的優勢的，氣壓熱成形簡單而言就是超塑性成形(SPF)或為快塑成形(QPF)，前者的製程條件:1.細晶超塑性材料2.超塑成形溫度3.超塑成形變形速率，而後者則為衍生出專為汽車工業採用的工法。然而定義或者區別以及他們的成形性卻沒有明確的解釋與說明，大多數的金屬例如鋁合金、可分為細晶跟粗晶粒材料，這種微結構所具備的成形條件、即溫度和應變速率，在氣壓成形過程中就可以被分類為超塑性或者非超塑性材料，本論文中對於鋁合金5083超塑性及非超塑性材料分別在不同需求的成形模具內，觀察其成形性進行比較，也對於超塑性成形與快塑成形兩者製程的成形性做比較，結果顯示超塑性成形適合複雜且較難以成形的零件、而在形狀簡單的模具下其厚度分佈也比快塑成形優秀，但此氣壓成形工法的條件較為嚴謹、必須要在符合的溫度(~500℃)、應變速率(一般條件約為10-3~10-4 S-1)之外、更需要具備足夠的成形空間(模具設計)以及超塑性材料(細晶粒 5~10µm)，才能完全展現超塑性成形的特色，而在快塑成形中，則可以藉由較大的變形速率完成較為一般的成形零件、其成形要求的溫度較低(~450℃)、應變速率為~10-2 S-1快了超塑性成形將近10倍的速度，表示了兩種氣壓成形工法分別在不同的需求上，有著各別的優缺條件以及重要性。

關鍵字

超塑性成形 ； 快塑成形 ； 鋁合金5083

並列摘要

Abstract
Low pressure gas forming in the industry is an advantage, low pressure gas forming simply, is superplastic forming (SPF) or Quick Plastic Forming (QPF). However, their definitions or distinction together with their formability have not been stated or explained well. Most metals including aluminum alloy, can be either fine or coarse grained. This original microstructures together with specific forming conditions, i.e. temperature and strain rate, determine whether the sheet gas forming process is classified as a superplastic or a non-superplastic one. For this paper superplastic and non-superplastic 5083 aluminum alloy materials are different needs in the mold, comparing observed formability, but also for forming superplastic forming and quick plastic forming process both of compare, the results show superplastic forming for complex parts and forming more difficult, and in the shape of a simple mold having a thickness distribution of excellent faster than quick plastic forming, The results show superplastic forming for forming complex and more difficult parts, but in the shape of a simple mold thickness distribution is better than quick plastic forming, but this gas forming conditions more stringent, must be in compliance with the temperature (~ 500 ℃), strain rate (~ 10-3 ~ 10-4 S-1), more need to have enough space forming (mold design) and superplastic materials (fine-grained 5 ~ 10μm), in order to fully demonstrate the characteristics of superplastic forming, and in quick plastic forming, which forming the required lower temperature (~ 450 ℃), strain rate of ~ 10-2 S-1 , it’s than superplastic forming nearly 10 times faster, gas forming respectively represent two different needs, have their advantages and disadvantages as well as the importance.

並列關鍵字

Superplastic forming (SPF) ； Quick plastic forming (QPF) ； AA5083

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