臺灣博碩士論文加值系統

現今精密機械所使用之傳動元件，如線性滑軌與滑塊等，皆需要很高的真直度和形狀精度，此類傳動元件之尺寸精度會影響平台操控的精度，並影響後續加工以及儀器量測的精度，其機械加工的前製程為輥軋或抽拉成形加工。而冷間精抽通常實施於多道次輥軋預成形後，或於多道次抽拉為預成形後，再以預成形進行最終小面縮率的抽拉，此類形材截面可視為多塊矩形組成，而對於矩形材的抽拉成形而言，其寬度與厚度方向可能有不同縮率，以及不同的眼模半角的組合，若嘗試以田口法來尋求最佳眼模半角值，往往需要相當大的模擬量。

本研究先將形材抽拉製程簡化為矩形材之抽拉，首先藉由有限元素套裝軟體DEFORM-3D來模擬方形材的表面精抽製程，探討不同眼模半角、面積縮率的組合對成形負荷之影響，並定義平均應變差，以計算工件抽拉後的變形不均度，再藉由此方形材之表面精抽製程的學理基礎，本研究提出矩形材精抽為方形材之最佳眼模半角選用準則，並以DEFORM-3D軟體模擬，進行抽拉成形負荷的驗證，以及估算工件變形的均勻度。

由模擬結果驗證，當矩形工件進行寬度縮率與厚度縮率不等之抽拉，且工件出口截面為正方形時，其在寬度與厚度方向之最佳眼模半角值範圍，將分別介於方形材在相同寬度與相同厚度抽拉時之最佳眼模半角，與寬度及厚度縮率之總合面縮率進行抽拉時之最佳眼模半角之間；矩形材抽拉之最佳眼模半角所對應之平均應變差，亦落在準則所預測之區間內。

Transmission components used in precision machines like rails or sliders for linear motion guide demand high straightness and shape precision. The precision of these components affect the precision of machine movement and subsequent machining or measuring precision. Prior to machining, workpiece for the rails or sliders has to be rolled or drawn. Cold skin-pass drawing is usually applied on the preform, which may be produced by multiple shape rolling or drawing, with light reduction of cross-section. The cross-section of the shaped workpiece can be considered to be comprised of rectangles. As for drawing with rectangles, there can be possible combinations of different thickness and die semi-angle along both the width and thickness directions. It would require tremendous amount of case simulation in searching of the optimum die semi-angle by Taguchi method.

In order to verify the guideline in selecting the optimum die semi-angles, this work first computed the drawing load of square bar by finite element simulation with DEFORM-3D under various combinations of die semi-angles and reduction of cross-section. Optimum angle can be obtained which yielded lowest drawing load for the same reduction. “Mean variation of effective strain” was defined in order to quantify the level of deformation inhomogeneity under the choice of various parameter combinations. The result of square drawing was further applied to the selection of optimum die semi-angles for drawing from rectangle to square, and corresponding deformation inhomogeneity was also verified with finite element simulation.

The finite element simulations verified that when drawing square to rectangle with different width and thickness reductions, the range of optimum die semi-angle in the width direction fell between the optimum angles in drawing square with the same width reduction and with same area reduction. While the range of optimum die semi-angle in the thickness direction fell between the optimum angles in drawing square with the same area reduction and with the same thickness reduction. The corresponding deformation inhomogeneity also fell in the range as predicted by this guideline.

摘　要 i
ABSTRACT iii
誌謝 v
目錄 vi
表目錄 viii
圖目錄 ix
第一章 緒論 1
1.1 前言 1
1.2 文獻回顧 3
1.3 研究目的 6
1.4 論文總覽 8
第二章 理論基礎與研究方法 9
2.1 抽拉成形基本原理 9
2.2 金屬成形之分析理論介紹 12
2.3 DEFORM軟體之簡介 16
2.4 表面精抽之模擬設定 17
第三章 方形材表面精抽模擬結果與討論 22
3.1 寬度與厚度方向使用相同眼模半角及縮率之方形材抽拉 23
3.1.1 最佳眼模半角 24
3.1.1.1 摩擦因子0.1 24
3.1.1.2 摩擦因子0.3 25
3.1.2 平均應變差 26
3.2 不同寬與厚度縮率矩形材之眼模半角選用法則與驗證 27
3.2.1 成形負荷之驗證 30
3.2.1.1 寬縮-厚縮率為10%-5% 30
3.2.1.2 寬縮-厚縮率為10%-7.5% 31
3.2.1.3 寬縮-厚縮率為10%-2.5% 32
3.2.1.4 寬縮-厚縮率為7.5%-5% 34
3.2.1.5 寬縮-厚縮率為7.5%-2.5% 35
3.2.1.6 寬縮-厚縮率為5%-2.5% 36
3.2.2 平均應變差之驗證 38
3.2.2.1 寬縮-厚縮率為10%-5% 38
3.2.2.2 寬縮-厚縮率為10%-7.5% 40
3.2.2.3 寬縮-厚縮率為10%-2.5% 42
3.2.2.4 寬縮-厚縮率為7.5%-5% 44
3.2.2.5 寬縮-厚縮率為7.5%-2.5% 46
3.2.2.6 寬縮-厚縮率為5%-2.5% 48
第四章 結論與建議 51
4.1 結論 51
4.2 建議 54
參考文獻 55
英文論文大綱 58

[1]M. Kobayashi, The present situation of cold drawn special sections, Journal of the JSTP, Vol. 39, N0. 447 (1998) 335-337.
[2]H.S. Lin, Y.C. Hsu, C.C. Keh, “Inhomogeneous deformation and residual stress in skin-pass axisymmetric drawing,” Journal of Materials Processing Technology 201 (2008) 128-132.
[3]K. Yoshida, S. Tuihiji, “Multiple drawing of rails for linear motion guide,” Advance technology of plasticity, Vol. 1, Oct. 28-31, 2002, Yokohama, Japan.
[4]S.K. Lee, J.E. Lee, B.M. Kim and S.M. Kim “Die design in the complex- shape drawing of cross roller guide to improve the dimensional accuracy,” Proceedings of the 10th Advances in Materials and Processing Technologies, Oct. 7-11, 2007, Daejeon, Korea, pp. 302-310.
[5]B.B. Basily, D.H. Sansome, “Some theoretical considerations for the direct drawing of section rod from round bar,” International Journal of Mechanical Science, 18 (1976) 201-208.
[6]C.B. Boër, W.R. Schneider, B. Eliasson, B. Avitzur, “An upper bound approach for the direct drawing of square section rod from round bar,” Proceedings of 20th International Machine tool design and research conference, Birmingham, 1979, pp. 149-156.
[7]L. Bayoumi, “Round-to square section drawing through flat idle rolls,” International Journal of Mechanical Science, 41 (1999) 1323-1338.
[8]Y.C. Kim, B.M. Kim, “A study on the corner filling in the drawing of a rectangular rod from a round bar,” International Journal of Machine Tools & Manufacture, 40 (2000) 2099-2117.
[9]Steuff, W. and Kopp, R., “Estimation of designing methods for the drawing of section rods and wire,” Wire J. International, Vol. 28, No. 3 (1995), 104-109.
[10]J.R. Renz, R. Kopp, “A new calibration method for complex shape sections with reflex angles,” Wire J. International, Vol. 31, No. 11 (1998), 96-100.
[11]范光堯，生醫用鈦合金異型材抽拉製程的開發，國科會專題研究計畫成果報告，計畫編號：NSC92-2622-E-005-008-CC3。
[12]許源泉，塑性加工學，全華科技圖書股份有限公司，民國93年。
[13]黃新春、陳昌順、王進猷，塑性加工學，文京圖書股份有限公司，民國88年。
[14]賴耿揚，抽線抽管塑性加工，復漢出版社，民國85年。
[15]李榮顯，塑性加工學，三民書局，民國75年。
[16]W. F. Hosford and R. M. Caddell, “Metal Forming, Mechanics and Metallurgy,” Prentice Hall, 1983.
[17]M. L. Devenpeck, O. Richmond, “Strip-drawing experiments with a sigmoidal die profile,” Journal of Engineering for Industry, November (1965) 425 - 428.
[18]DEFORM User’s Guide, “Scientific Forming Technologies Corporation,” Columbus OH, 2007.
[19]陳俊豪，有限元素法導論，科技圖書股份有限公司，台北，臺灣，pp. 155~183，1992年12月。
[20]蘇品書，材料加工力學解析，復漢出版社，台南，臺灣，pp.36~40，pp. 127~147，1992年12月。
[21]S. Kobayashi, S.I. Oh and T. Altan, “Metal Forming and The Finite element Method,” Oxford university press, New York, 1989.
[22]李俊賢，具高深寬比深微孔精微零件之擠壓成形研究，國立虎尾科技大學機械與機電工程研究所碩士論文，雲林，臺灣，2005年7月。
[23]管金談、許源泉，DEFORM鍛造模擬解析實務，國立虎尾技術學院機械製造工程系成形實驗室，民國89年。
[24]有限元素法DEFORM鍛造成形軟體操作手冊。
[25]蔡盛祺主編，鍛造模具設計手冊，金屬工業研究發展中心，民國87年。