摘 要

本文針對退火處理過之AA6063-T5鋁合金管材，利用萬能試驗機台與管材液壓成形實驗機台，進行板金成形性試驗與液壓鼓脹成形試驗。藉由電化學網格蝕刻與影像量測處理系統，建立材料之成形極限圖(Forming Limit Diagram, FLD)。另外，以Hill的新降伏準則塑性不安定判別式預測金屬材料之成形極限曲線(Forming Limit Curve, FLC)，將理論所預測之成形極限圖與實驗所量測之成形極限圖互相比較驗證。最後，比較板材與管材之成形極限圖可知，兩者之成形極限相當一致。而Hill新降伏準則所預測之成形極限曲線與實驗值比較，結果顯示相當吻合，所以可作為板金或管材成形極限曲線之判別式。

ABSTRACT

The objective of this study is to establish the Forming Limit Diagram (FLD) of tubes. An experimental system of tube hydroforming, the electrical chemical etching method and the image process system are used to carry out the sheet metal forming test and the hydraulic bulge-forming test of annealed aluminum alloy tubes. Furthermore, Hill’s new yield criterion is also used to predict the Forming Limit Curves of sheets. The predicted forming limit diagrams are compared with experimental data. The forming limit diagrams of tubes are coincident with those of sheets. Also, the predicted forming limit curves by Hill’s new yield criterion agree quite well with those by experiments. Therefore, Hill’s new yield criterion can be used to establish the forming limit curves of sheets or tubes.

目 錄

中文論文摘要 Ⅰ
英文論文摘要 Ⅱ
目錄 Ⅲ
表目錄 Ⅵ
圖目錄 Ⅶ
符號說明 Ⅹ
第一章 緒論 1
1-1 前言 1
1-2 製程簡介 2
1-2-1 管材液壓鼓脹成形技術 2
1-2-2 板金沖壓成形技術 3
1-3 文獻回顧 4
1-3-1 管材液壓成形極限之相關文獻 4
1-3-2 板金沖壓成形極限之相關文獻 6
1-4 本文研究範疇 8
1-4-1 本研究之目的 8
1-4-2 本論文之架構 8
第二章 理論分析 12
2-1 基本假設 12
2-2 座標系定義 13
2-3 塑性力學準則 13
2-3-1 基本塑性力學方程式 13
2-3-2 塑性不安定準則 14
第三章 材料拉伸試驗 22
3-1 目的 22
3-2 強度係數與應變硬化指數之測定 22
3-3 正向異向性之測定 23
3-4 材料拉伸試驗結果 25
3-4-1 強度係數與應變硬化指數 25
3-4-2 正向異向性 26
第四章 管材成形極限圖之建立 33
4-1 成形極限圖簡介 33
4-2 成形極限試驗之目的 34
4-3 實驗管材與試片之準備 34
4-3-1 管材之退火處理 35
4-3-2 管材圓形試片之截取 35
4-3-3 電化學網格蝕刻 36
4-4 板金成形性試驗 36
4-5 液壓鼓脹成形性試驗 37
4-5-1 實驗設備 37
4-5-2 實驗步驟 38
4-6 網格影像量測處理 38
4-7 管材成形路徑之有限元素模擬 40
4-7-1 DEFORMTM簡介 41
4-7-2 DEFORMTM之分析模式 42
第五章 結果與討論 58
5-1 板金成形性試驗結果 58
5-2 液壓鼓脹成形性試驗結果 58
5-3 應用塑性不安定準則預測成形極限曲線 59
5-3-1 以塑性不安定準則預測成形極限曲線 59
5-3-2 材料性質參數對塑性不安定準則之影響 60
5-4 成形路徑模擬結果 62
5-4-1 板金成形性路徑模擬 62
5-4-2 液壓鼓脹成形路徑模擬 64
第六章 結論 86
6-1 研究成果總結 86
6-2 今後研究課題 87
參考文獻 89
附錄 等效應變增量與應變增量關係式之推導 94
自述 98

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