本文針對鎂合金薄板及薄管之熱間擠製進行解析及實驗之研究。首先進行熱間壓縮試驗，以獲得鎂合金在高溫時之塑流應力。接著使用有限元素分析進行薄板及薄管之熱間擠製模擬。在薄板擠製解析方面，找出合適模具軸承長度設計、初始鎂錠溫度及擠速控制以獲得健全薄板。此外，經由擠製速度對模具出口產品溫度之影響，找出欲達等溫擠製之擠製速度變化圖。在薄管擠製解析方面，分析鎂錠從分流孔、銲合室至模具軸承部之流動型態，探討模具之彈性變形，並藉由擠製條件之適當控制，以獲得健全之薄管。最後進行熱間擠製實驗，由擠製荷重及產品尺寸等解析值與實驗值之比較，驗證解析模式之適用性。

This study involves analyses and experiments of magnesium’s hot extrusion of thin sheets and tubes. At first, hot compression tests are conducted to obtain the magnesium’s plastic flow stresses in high tempearatures, which will be used in the finite element analysis. In the FE simulations of thin sheet extrusion, the flow pattern of the magnesium billet within the die, the temperature history at die exit and the elastic deformation of the die is analyzed. Sound and good thin sheets are obtained by appropriate die design, initial billet temperature and extrusion velocity’s control. The goal of constant temperature extrusion is expected to achieved by controlling the extrusion velocity which will influences the billet temperature at die exit. In FE simulations of thin tube extrusion, the flow pattern of the magnesium billet within the port-holes, welding chamber and die bearing is analyzed. The elastic deformation of the die is dicussed. Extrusion of sound thin tubes is achieved by appropriate extrusion conditions. Finally, hot extrusion experiments are conducted and the experimental values of the extrusion load and dimensions of the products are compared with the analytical values to verify the validity of the analytical models.

目錄 II
表目錄 V
圖目錄 VI
摘要 X
第一章 緒論 1
1-1 前言 1
1-2 擠製加工製程簡介 6
1-3 鎂合金擠製加工成形法之優勢 8
1-4 鎂合金擠製加工技術之影響參數 9
1-5 文獻回顧 10
1-5-1 鎂合金擠製之相關文獻 10
1-5-2 鋁合金擠製之相關文獻 13
1-6 研究目的 18
第二章 薄板擠製有限元素分析 20
2-1 鎂合金AZ31熱間壓縮試驗 20
2-2 鎂合金AZ31薄板擠製模擬之模組建立 26
2-2-1 有限元素分析軟體DEFORM-3D簡介 26
2-2-2 鎂合金薄板擠製之模型建立 27
2-3 鎂合金AZ31薄板擠製之模擬參數設定 29
2-4 鎂合金AZ31薄板擠製之製程參數研究 32
2-4-1 模具軸承設計之探討 32
2-4-2 初始擠錠溫度之探討 39
2-4-3 擠製速度之探討 43
第三章 薄管擠製有限元素分析 48
3-1 鎂合金AZ31薄管擠製有限元素分析之模組建立 48
3-1-1 薄管之幾何尺寸與擠製模型建立 48
3-1-2 分流孔、心軸與銲合室之設計 50
3-1-3 模具軸承部之設計 52
3-2 鎂合金AZ31薄管擠製之製程參數研究 53
3-2-1 擠製參數設定 53
3-2-2 初始擠錠溫度之探討 53
3-2-3 擠製速度之探討 56
第四章 鎂合金熱間擠製實驗 60
4-1 實驗設備及流程 60
4-1-1 擠製機台簡介 61
4-1-2 擠製實驗流程簡介 64
4-2 模具之設計及製作 66
4-2-1 薄板模具之設計與製作 66
4-2-2 空心薄管模具之設計與製作 72
4-3 擠製實驗參數之設定 74
4-3-1 厚度1.50mm薄板擠製實驗參數之設定 74
4-3-2 厚度1.00mm薄板擠製之實驗與模擬參數設定 74
4-4 解析值與實驗值之比較 76
4-4-1 厚度1.50mm薄板擠製之解析值與實驗值之比較 76
4-4-2 厚度1.00mm薄板擠製之解析值與實驗值之比較 80
第五章 結論 84
5-1 厚度1.50mm薄板擠製之有限元素解析 84
5-2 厚度1.50mm及1.00mm薄板擠製之實驗 85
5-3 厚度1.00mm空心薄管擠製之有限元素解析 86
5-4 未來展望 86
參考文獻 88

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