鎂合金除了用於電子資訊3C產品之外，亦開始被使用在汽車、飛機及鐵路車輛等工業領域。鎂合金板材於熱間壓延時，其晶粒大小的演化、集合組織的變化，壓延後成形性的探討等，為重要的研究課題。本研究將進行鎂合金板材熱間壓延技術之開發。使用材料為AZ31，透過電阻式加熱及輥輪冷卻系統之設計，及壓延條件的控制，以達到板材入口溫度之恆溫壓延及晶粒細化之目標。
第一部分進行一系列鎂合金板材之拉伸試驗，以求得不同應變率及不同溫度下之塑流應力。同時，利用有限元素模擬，分析鎂合金板材在輥隙內之流動形態，並探討所需壓延壓力及板材溫度分佈，以協助板材晶粒大小之預測。第二部分進行鎂合金板材熱間壓延實驗，探討壓延後板材之微觀組織，是否達到晶粒細化及改善機械性質之目標。最後由壓延負載及板材出口溫度等解析值與實驗值比較，驗證解析模式之適用性。

Magnesium alloy products have not only been applied to electronic information and 3C industries products, but also applied to automobiles, airplanes and rail car bodies. During hot rolling of magnesium alloy sheets, the investigations of the grain revolution, texture variation and the formability of the rolled product, etc., are important research topics. This project will develop the hot rolling technologies of various magnesium alloy sheets. Magnesium alloys AZ31 is used as the sheets. Using an electric resistance heating system, a self-designed roll cooling system, and appropriate rolling conditions, the goals of keeping the sheet in the entry a constant temperature during the rolling processes and fine grain sizes in the rolled products can be achieved.
First, a series of tensile tests of magnesium alloy sheets are conducted to obtain the flow stresses of the sheets under different strain rates and different temperatures. At the same time, by the finite element simulation, the flow pattern of the magnesium alloy sheet within the roll gap is analyzed. The rolling force needed and sheet temperature distributions are discussed, which is helpful for the prediction of the grain sizes of the rolled sheets. Secondly, hot rolling experiments of magnesium alloy sheets are conducted. Microstructure of the rolled products are discussed to check if the goals of fine grain sizes, and improvement of the mechanical properties are achieved. Finally, the experimental values of the rolling load and the exit temperature of the sheet are compared with the analytical values to verify the validity of the analytical models.

論文審定書 ii
謝 誌 iii
摘 要 iv
Abstract v
目錄 vi
圖目錄 x
表目錄 xv
符號說明 xvii
第一章 緒論 1
1-1 前言 1
1-2 鎂合金在生活上的應用 2
1-3壓延機的種類 4
1-3-1壓延加工原理: 4
1-3-2近代壓延加工技術之發展: 5
1-3-3目前發展中壓延加工技術 5
1-3-4壓延過程中晶粒的變形與成長: 6
1-3-5金屬強化 7
1-4 文獻回顧 9
1-4-1鎂合金擠型加工之相關文獻: 9
1-4-2鎂合金壓延加工之相關文獻: 9
1-4-3晶粒尺寸數學模型之相關文獻: 10
1-5本文架構 11
第二章AZ31恆溫壓延之有限元素分析 13
2-1 鎂合金板材熱間單軸拉伸試驗 13
2-1-1實驗步驟 13
2-1-2拉伸試片之製作與拉伸參數之規劃 14
2-1-3塑流應力之求得 16
2-1-4應變硬化指數、應變率敏感係數與強度係數之求得 18
2-2鎂合金AZ31熱間壓延模型建立 25
2-2-1 有限元素分析軟體介紹 25
2-2-2鎂合金AZ31熱間壓延之模擬基本參數之設定 26
2-3不同壓延之條件參數下對壓延力的影響 30
2-3-1不同壓延力探討 30
2-3-2不同壓下率對等效應變關係 32
2-3-3不同壓下率對金屬流動速度關係 33
2-3-4不同輥速對等效應變率之影響 34
2-4熱間壓延與板材溫度之探討 37
2-4-1電爐式與電阻式加熱法應用於壓延加工法之比較 37
2-4-2考慮熱傳效應對板材壓延力的影響 42
2-4-3熱傳效應對入口與出口溫度之關係 44
2-4-4綜合結果討論 46
第三章 壓延加工實驗與分析 48
3-1鎂合金板材之壓延前熱處理 49
3-1-1 AZ31之成分 49
3-1-2 AZ31均質化處理 50
3-1-3冷間壓延機簡介 54
3-1-4板材及輥輪加熱系統 55
3-1-5輥輪冷卻系統與進水口迴轉接頭之設計 56
3-2鎂合金壓延實驗 58
3-2-1實驗步驟 58
3-2-2荷重計校正 60
3-2-3實驗結果分析 61
3-2-4板材壓下率的影響 63
3-3解析值與實驗值之比較 64
第四章 鎂合金熱間壓延後金相觀察、硬度試驗及機械性質測試 69
4-1金相觀察試驗之分析 69
4-1-1金相試驗之規劃 69
4-1-2金相試驗 69
4-1-3晶粒尺寸量測 71
4-1-4熱間壓延對晶粒尺寸的影響 71
4-2硬度量測之分析 77
4-2-1實驗設備介紹 78
4-2-2實驗規劃 81
4-2-4壓延後對板材硬度的影響 81
4-3進行T5熱處理及常溫單軸拉伸試驗 87
4-3-1實驗步驟 87
4-3-2 T5熱處理後對抗拉強度、伸長量之探討 88
4-3-3 T5熱處理後板材表面硬度及微觀組織 89
第五章 結論與未來展望 94
5-1 熱間壓延之有限元素分析 94
5-2 鎂合金之熱間壓延實驗分析 95
5-3微觀組織與機械性質測試 95
5-4未來展望 96
參考文獻 97

[1] 歐珍方, ”材料科學與工程” , 歐亞書局
[2] Y. Chino, X. Huang, K. Suzuki, M. Mabuchi, “Enhancement of Stretch Formability at Room Temperature by Addition of Ca in Mg-Zn Alloy” , Mater. Trans., Vol.51, pp.818-821(2010)
[3] 野田 雅史, 酒井 直人, 船見 国男, 森 九史, 藤野 謙司, “Mg-3Al-1Zn-1Ca合金の圧延加工よる結晶微細化と高強度化”, 日本塑性加工学会誌, 塑性と加工, Vol54. No.625, pp.143-147 (2013)
[4] 木内 学,　“連続鋳造と圧延とのプロセスフュ一ジョン”, 日本塑性加工学会誌, 塑性と加工, Vol44. No.508, pp.501-505 (2003)
[5] W. Yuan, S.K. Panigrahi, J.-Q. Su, R.S. Mishra, ”Influence of grain size and texture on Hall-Petch relationship for a magnesium alloy” , Scripta. Mater. ,Vol.64, pp. 994-997(2011)
[6] 崛 茂德, 浜野 勇, 長火田 一拓, 田村 健, 阿倍 睦, 田井 英男, 輕金屬, Vol44, pp.231(1994)
[7] Material Handbook , Vol 4 Heat Treating, pp.744-753
[8] 蔡浩然, ”AZ91鎂合金之熱處理與表面處理研究” , 碩士論文 國立東華大學(2007)
[9] Y. Uematsu, K. Tokaji, M. Kamakura, K. Uchida, H. Shibata, N. Bekku, ”Effect of extrusion conditions on grain refinement and fatigue behaviour in magnesium alloys” , Mater. Sci. Eng. A., Vol.434, pp. 131-140 (2006)
[10] H. Zhang, Q. Yan, L. Li, ”Microstructures and tensile properties of AZ31 magnesium alloy by continuous extrusion forming process” , Mater. Sci. Eng. A., Vol.486, pp. 295–299 (2008)
[11] Y. Chen, Q. Wang, J. Peng, C. Zhai, W. Ding, ”Effects of extrusion ratio on the microstructure and mechanical properties of AZ31 Mg alloy” , J. Mater. Process. Technol. A., Vol.182, pp. 281–285 (2007)
[12] W. Tang, S. Huang, S. Zhang, D. Li, Y. Peng, ”Influence of extrusion parameters on grain size and texture distributions of AZ31 alloy” , J. Mater. Process. Technol. A., Vol.211, pp.1203 -1209 (2011)
[13] A. Galiyev, R. O. Sitdikov, R. Kaibyshev, “Deformation Behavier and Controlling Mechanisms for Plastic Flow of Magnesium and Magnesium Alloy” , Mater. Trans., Vol42, p.426-435(2003)
[14] 行武栄太郎, "マグネシウム合金板材の塑性変形特性および加工技術の研究”,塑性と加工, Vol.53, No.623, p.52 (2012)
[15] 片平卓志, 細川翔平, 中 哲夫, 高津正秀, 足立大樹, 吉田総仁, "AZ31合金の双晶変形に及ぼす集合組織の影響” , 塑性加工春季講演会, pp.33-34 (2013)
[16] 浜田 剛, 橋本旭令, 渡部揚平, 左海哲夫, 宇督宮 裕, "AZ31 マグネシウム合金板材の圧延加工性に及ぼす圧延速度の影響" , 塑性加工春季講演会, pp.235-236 (2009)
[17] 郭麗麗, 藤田丈夫, 陳中春, 兼子 毅, 阿部友樹, ”圧延によるAZ31 マグネシウム合金の結晶粒微細化及び集合組織変化と成形性” , 塑性加工春季講演会, pp.241-242 (2009)
[18] H. Zhang, G. Huang, L. Wang, H. J. Roven, F. Pan, ”Enhanced mechanical properties of AZ31 magnesium alloy sheets processed by three-directional rolling” , J. Alloy Comp., Vol.575, pp. 408-413 (2013)
[19] 高津正秀, 西尾浩之, 東 健司, 喜井健二, 辻川正人, 井上博史, “圧延と高温焼鈍によるAZ31マグネンウム合金板の集合組織ランダム化挙動” , 塑性加工春季講演会(2009)
[20] 阿高松男, 安藤紅巴, 長瀨健太郎, ”マグネシウム合金の圧延性の向上” , 塑性加工春季講演会, pp.373-374 (2009)
[21] M. Bagherupoor, H. Bisadi, ”Effects of rolling parameters on temperature distribution in the hot rolling of aluminum strips” , Appl. Therm. Eng., Vol.31, p.1556-1565 (2011)
[22] M. P. Guerrero, C. R. Flores, A. Pérez, R. Colás, ”Modelling heat transfer in hot rolling work rolls” , J. Mater. Process. Technol., Vol.94, pp.52-59 (1999).
[23] W. L. Chen, Y. C. Yang, ”Inverse problem of estimating the heat flux at the roller/workpiece interface during a rolling process” , Appl. Therm. Eng., Vol.30, pp.1247-1254 (2010)
[24] Z. Q. Sun, W. Y. Yang, J. J. Qi, A. M. Hu, ”Deformation enhanced transformation and dynamic recrystallization of ferrite in a low carbon steel during multipass hot deformation” , Mater. Sci. Eng. A., Vol.334, pp.201-206 (2002)
[25] Y. Qin, Q. Pan, Y. He, W. Li, X. Liu, X. Fan, ”Hot compression behavior and flow stress prediction of ZK60 magnesium alloy ” , Acta. Metall. Sin., Vol.45, p.887-891 (2009)
[26] B. K. Chen, H. N. Kha, ”Development of hot rolling practices for lithographic sheet using a thermo-mechanical and microstructural model of a reversing hot finishing mill” , J. Mater. Process. Technol. , Vol.152, pp.221-227 (2004)
[27] S. Serajzadeh, ”Prediction of microstructural changes during hot rod rolling” , Int. J. Mach. Tools Manuf., Vol.43, pp.1487-1495 (2003).
[28] M. A. Razzak, M. Perez, T. Sourmail, S. Cazottes, M. Frotey, ” A simple model for abnormal grain growth” , ISIJ Int., Vol. 52, No.12, pp.2278–2282 (2012)
[29] F. Sui, Y. Zuo, X. Liu, L. Chen, ”Microstructure analysis on in 718 alloy round rod by FEM in the hot continuous rolling process” , Appl. Math. Model, pp.8776-8784 (2013)
[30] C. Sun, J. Luan, G. Liu, R. Li, Q. Zhang, ”Predicted constitutive modeling of hot deformation for AZ31 magnesium alloy” , Acta. Metall. Sin., Vol.48, pp.853-860 (2012)
[31] 岩田隆道, 上山道明, 与語康宏, 岩田徳利, 石川孝司, 鈴木克幸 ”リング圧縮試験の薄板形状への適用方―薄鋼板の高ひずみ域の変形抵抗の測定” , 塑性と加工, Vol.54, No.632, p.58-62 (2013)
[32] 陳信吉, ”AZ系鎂合金沖鍛成形之研究” , 碩士論文 國立台灣大學(2003)
[33] K. Yu, X. Y. Wang, Z. Y. Cai, R. C. Wang, D. Shi, ”Finite element simulation of deformation in hot rolling process of AZ31 magnesium alloy” , Journal of Central South University(Science and Technology)., Vol.140, pp.1535-1539(2009)
[34] http://www.matweb.com
[35] D. Wan, J. Wang, G. Wang, L. Lin, Z. Feng, G. Yang, ”Precipitation and responding damping behavior of heat-treated AZ31 magnesium alloy” , Acta. Metall. Sin., Vol.22, pp.1-6 (2009)