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研究生： 林澤龍
Tzer-Long Lin
論文名稱： 金屬粉末射出成形毛細吸附脫脂
Investigation of Wick Debinding in Metal Injection Molding:Numerical Simulations and Experiments
指導教授： 洪勵吾
Lih-Wu Hourng
口試委員:
學位類別： 博士
Doctor
系所名稱： 工學院 - 機械工程學系
Department of Mechanical Engineering
畢業學年度： 93
語文別： 中文
論文頁數： 133
中文關鍵詞： 金屬粉末射出成型 、最大熵方法 、局部空孔度分佈
外文關鍵詞： metal powder injection molding, maximum entropy
相關次數： 點閱：8  下載：0 
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    • 金屬粉末射出成型能夠製造形狀複雜、機械性質優良之淨尺寸工件，其製造程序中以脫脂為最關鍵製程，各種脫脂方法中，毛細吸附脫脂方法可明顯縮短製程時間，因此成為重要的產業技術。事實上，胚體/吸附材的空孔度是隨著控制體積改變而改變，但是文獻上很少人研究，「如何量測這些空孔度分佈情形」以及這些「隨著控制體積改變而改變的空孔度」，如何影響整個脫脂過程。本研究將引用「局部空孔度分佈」概念，並從空孔結構圖像來量測空孔度分佈情形。利用最大熵方法來決定「最適宜空孔度分佈」及「特徵長度」，應用適合度檢定方法，找出最適宜「理論分佈函數」。根據此「理論分佈函數」，藉由「亂數產生器」產生大量空孔度數據，代入數值程式中模擬，其中「特徵長度」將是控制體積邊長依據。數值模擬結果發現，吸附材之潤濕邊界會隨機化的移動擴張，其外輪廓線亦相當不規則，整個脫脂時間與胚體半徑成線性關係。此外，本研究也成功完成一系列實驗，觀察到潤濕邊界移動擴張的情形，並量測脫脂時間、黏結劑在胚體殘留量和在吸附材內之填充量。

    Metal powder injection molding (MIM) can manufacture parts of net-shape with intricate contour as well as mechanical properties. The debinding stage is a critical process. The wick debinding can reduce the debinding cycle time and is a crucial technique. The porosity of the compact/wick varies with control volume, but there are few literatures in determining the porosity distribution of the compact/wick and how the porosity varying with control volume affects the wick debinding process. A local porosity distribution (LPD) is quoted and measured from the digital image of pore structure. Applicable LPDs and typical length scales are then calculated by maximum entropy method (MEM). Proper theoretical porosity distribution functions are adopted to fit the applicable LPDs. According to the theoretical distribution function, a random number generator is used to generate data of porosity with quantitative randomness for numerical simulations. The typical length scale is an important basis for determining the size of the control volume (or grid). The porosity distributions are used in simulations and show the walking flow edges behave randomly, the contours of wetting wick are irregular and the total debinding time is linearly dependent on the radius of the compact. Besides, an experiment has successfully been developed that can observe the phenomenon of the walking flow edges, measure the total debinding time and calculate the percentages of residual binder and the pore space filled. The numerical results agree well with the experimental results.

    授權書 Ⅰ 推薦書 Ⅱ 審定書 Ⅲ 摘要 Ⅳ 英文摘要 Ⅴ 目錄 Ⅶ 表目錄 Ⅸ 圖目錄 Ⅹ 符號說明 ⅩⅢ 第一章、緒論 1-1 前言 1 1-2 文獻回顧 3 1-3 研究方向 8 第二章 量測最適宜空孔度分佈 2-1 定義與原理 12 2-2 試片製作準備 20 2-3 計算局部空孔度分佈 23 2-4 局部空孔度分佈適合度檢定 24 2-5 結果與討論 25 第三章 數值方法 3-1 定義與原理 27 3-2 數值模式建立 33 3-3 數值分析 37 3-4 數值流程 39 3-5 估算理論脫脂時間 40 第四章 量測脫脂時間 4-1實驗設備與材料 44 4-2實驗程序 45 4-3實驗注意事項 46 第五章 結果與討論 5-1數值模擬結果 48 5-2脫脂實驗結果 50 5-3討論 52 第六章 結 論 54 參考文獻 56 表 63 圖 66 附錄 A Derivation of Shannon’s entropy 108 附錄 B Derivation of Boltzmann’s entropy 111 表 目 錄 表號 名稱 頁碼 表2-1 鐵金屬粉末物理性質表 63 表3-1 黏結劑(臘)物理性質表 64 表4-1 鋁金屬粉末物理性質表 65 圖 目 錄 圖號 圖名 頁碼 圖 1-1 毛細吸附脫脂示意圖 66 圖 1-2 空孔度量測流程圖 67 圖 2-1 晶格示意圖 68 圖 2-2 (a)有序排列與(b)紊亂排列示意圖 69 圖 2-3 熵與亂度關係圖 70 圖 2-4 試片製作流程圖 71 圖 2-5 胚體製作模具圖 72 圖 2-6 胚體空孔結構圖 73 圖 2-7 空孔度計算方式示意圖 75 圖 2-8 K-S適合度檢定示意圖 76 圖 2-9 局部空孔度分佈與量測長度關係圖 77 圖 2-10 熵與量測長度關係圖 79 圖 2-11 特徵長度下局部空孔度分佈圖 81 圖 2-12 實際與理論局部空孔度分佈比較圖 83 圖 2-13 實際空孔度分佈圖(Type-A) 85 圖 2-14 亂度產生器產生之空孔度分佈圖 (Beta分佈，a=1.3，b=0.85) 86 圖 3-1 曲面上表面張力所造成的壓力差 87 圖 3-2 毛細提升圖 88 圖 3-3 雷文瑞特 函數隨飽和度變化情形 89 圖 3-4 液體潤濕示意圖 90 圖 3-5 有限擴散聚集示意圖 91 圖 3-6 達西實驗中雷諾數對摩擦因子關係 92 圖 3-7 物理與計算區域示意圖 93 圖 3-8 控制體積與滲透度跳躍介面示意圖 94 圖 3-9 網絡格子與連絡通道示意圖 95 圖 3-10 數值計算流程圖 96 圖 3-11 理論估算之總脫脂時間與胚體變化關係圖 97 圖 4-1 觀察毛細吸附脫脂過程之實驗裝備示意圖 98 圖 5-1 使用Beta空孔度分佈，脫脂量6.08%時，胚體/吸附材區域的壓力分佈圖 99 圖 5-2 完全脫脂後潤濕吸附材之外輪廓線(使用Beta空孔度分佈)圖 100 圖 5-3 使用均一空孔度分佈，脫脂量12.16%時，胚體/吸附材區域的壓力分佈圖 101 圖 5-4 完全脫脂後潤濕吸附材之外輪廓線(使用均一空孔度分佈)圖 102 圖 5-5 數值模擬計算時總脫脂時間與胚體半徑大小關係圖 103 圖 5-6 在脫脂時間百分比為1.57%, 4.72%, 7.87%, 17.32% 及 100%時之吸附材潤濕的外輪廓線。 104 圖 5-7 觀察實驗之總脫脂時間與胚體半徑變化關係圖 105 圖 5-8 不同粉末胚體脫脂後比較圖 106 圖 5-9 總脫脂時間與胚體半徑變化關係圖 (四種條件：理論估算、空孔度成beta與均一分佈之數值模擬結果、實際實驗量測) 107

    1. R. M. German, Powder injection molding: current and long term outlook, The International, 36, 31-36 (2000).
    2. A. D. Hansonand S. C. Perruzza, Optimizing component designs for metal injection molding, Int. J. Powder Metall., 36, 37- 42 (2000).
    3. R. T. Fox and D. Lee, Optimization of metal injection molding: experimental design, Int. J. Powder Metall., 26, 233- 243 (1990).
    4. L. F. Pease, Present status of PM injection moulding (MIM) – an overview, MPR, 242-254 (1988).
    5. R. S. Libb, B. R. Patterson and H. A. Heilin, Production and evaluation of PM injection moulding feed stocks, MPR, 255-258 (1988).
    6. G. R. White and R. M. German, Effect of processing conditions on powder injection molded 316L stainless steel, Adv. in Powder Metall. & Part. Mater, 4, 185 (1994).
    7. K. M. Kulkarni, Dimensional precision of MIM parts underproduction conditions, Int. J. Powder Metall., 33, 29-41 (1997).
    8. M. Dutilly, O. Ghouati, J. C. Gelin, Finite-element analysis of the debinding and desification phenomena in the process of metal injection molding, J. Mater. Process. Tech., 83,170-175 (1998).
    9. J. R. Merhar, Overview of metal injection moulding, MPR, pp.339-342, 1990.
    10. K. M. Kulkarni, Metal powders and feedstocks for metal injection molding, Int. J. Powder Metall., 36, 43-52 (2000).
    11. B. K. Lograssso, A. Bose, B. J. Carpenter, C. I. Chung, K. F. Hens, D. Lee, S. T. Lin, C. X. Liu, R. M. German, R. M. Messler, P. F. Murley, B. O. Rhee, C. M. Sierra, and J. Warren, Injection of carbonyl iron with polyethylene wax, Int. J. Powder Metall., 25, 337-348 (1989).
    12. H. H. Angermann, F. K. Yang and O. van der Biest, Removal of low molecular weight components during thermal debinding of powder compacts, J. Mater. Sci., 27, 2534-2538 (1992).
    13. H. Zhang, R. M. German, and A. Bose, Wick debinding distortion of injection molded powder compacts, Int. J. Powder Metall., 26,217- 230 (1990).
    14. R. M. German, Theory of thermal debinding, Int. J. Powder Metall., 23, 237-245 (1987).
    15. B. K. Lograsso and R. M. German, Thermal debinding of injection molded powder compacts, Powder Metallurgy International, 22, 17-22 (1990).
    16. B. R. Patterson and C. S. Aria, Debinding injection molded materials by melt wicking, Journal of the minerals metals & materials Society, 41, 22- 24 (1989).
    17. C. S. Aria and B. R. Petterson, Influence of process variables on debinding by melt wicking, Modern Development in Powder Metallurgy,18, 403-416 (1988).
    18. R. Vetter, M. J. Sanders, I. Majewska-Glabus, L. Z. Zhuang and J.Duszczyk, Wick-debinding in powder injection molding, Int. J. Powder Metall., 30, 115-124 (1994).
    19. R. Vetter, W. R. Horninge, P. J. Vervoort, I. Majewska-Glabus, L. Z.Zhuang, J. Duszczyk, Squared root wick debinding model for powder injection moulding, Powder Metall., 37, 265-271 (1994).
    20. Y. C. Lam, Y. Shengjie, S.C.M. Yu and K. C. Tam, Simulation of polymer removal from a powder injection molding compact by thermal debinding, Metallurgical and Materials Transactions A, 31A, 2597-2606 (2000).
    21. C. C. Chen and L. W. Hourng, Basic permeability concepts related to wick debinding in metal injection moulding, Powder Metallurgy, 44, 117-122 (2001).
    22. C. C. Chen and L. W. Hourng, Numerical simulation of two dimensional wick debinding in MIM, Powder Metallurgy, 42, 313-319 (1999).
    23. M. S. Shih and L. W. Hourng, Random walk approach on study of void distribution during the resin transfer molding process, Journal of Reinforced Plastics and Composites, 23, 651-680 (2004).
    24. D.M. Mark and P.B. Aronson, Scale-dependent fractal dimensions of topographic surface: an empirical investigation with applications in geomorphology, Mathematical Geology, 16, 671-683 (1984).
    25. F. Boger, J. Feder, T. Jøssang, and R. Hilfer, Microstructural sensitivity of local porosity distributions, Physical A, 187, 55-70 (1992).
    26. E. Haslund , B. D. Hansen, R. Hilfer, and B. Nost, Measure of local porosities and dielectric dispersion for a water-saturated porous medium, J. Appl. Phys., 76, 5473-5480 (1994).
    27. R. Hilfer, Geometric and dielectric characterization of porous media, Physical Review, 44, 60-75 (1991).
    28. J. B. Jones and G. A. Hawkins, Engineering thermodynamics, Wiley, New York (1983).
    29. W. G. Vincenti and C. H. Kruger, Introduction to physical gas dynamics, Wiley, New York (1977).
    30. J. N. Kapur, Maximum entropy models in science engineering, Wiley, New York (1989).
    31. S. Ihara, Information theory for continuous system, Word-Scientific, Singapore (1993).
    32. C. Arndt, Information measures, Springer, New York (2001).
    33. L. L. Campbell, The relation between information theory and differential geometry approach to statistics, Information sciences, 25, 199-210 (1985).
    34. N. Wu, The maximum method, Springer, New York (1997).
    35. M. J. Kiemele and S. R. Schmidt, Basic statistics tools for continuous improvement, Air Academy Press, Springs, Colorado (1996).
    36. R. V. Hogg and J. Ledolter, Engineering statistics, New York, Macmillan, 1987.
    37. W. W. Daniel, Applied nonparametric statistics, PWS-KENT, Boston (1990).
    38. L. Devroye, Non-uniform random variate generation, Springer, New York (1986).
    39. P. E. Collins, Flow of fluids through porous materials, Chapman & Hall Ltd., London (1961).
    40. L. I. Osipow, Surface chemistry:theory and industrial application, Robert E. Krieger Publishing Company, Hungtington, New York (1972).
    41. W. Rose and W.A. Bruce, Evaluation of capillary characters in petroleum reservoir rock, Trans. AIME, 186, 127-142 (1949).
    42. R. B. Bird, R. C. Armstrong, Ole Hassager, Charles F. Curtiss, Dynamics of polymeric liquids- vol. 2, kinetic theory, Wiley Interscience (1987).
    43. T. A. Written and L. M. Sander, Diffusion-limited-aggreagtion, Phys. Rev. Lett. 27, 1400-1403 (1981).
    44. M. S. Shih and L. W. Hourng, Numerical simulation of capillary-induced flow in a powder-embedded porous matrix, Advanced Powder Technol., 12, 457-480 ( 2001).
    45. Rand Corporation, A million random digits with 100,000 normal deviates, Glencoe, IL: Free Press (1955).
    46. H. Zhang, R. M. German, and A. Bose, Wick debinding distortion of injection molded powder compacts, Int. J. Powder Metall., 26, 217- 230 (1990).
    47. Y. Bao and J. R. G. Evans, Kinetics of capillary extraction of organic vehicle from ceramic bodies. Part Ⅰ: Flow in porous media, Journal of the European Ceramic Society, 8, 81-93 (1991).
    48. W. S. Tchai, Experimental investigation on capillary pressure versus saturation relationship, Master’s Thesis, Mech. Eng. Dept., National Central University, Taiwan (2000).
    49. J. Bear, Dynamics of fluids in porous media, Dover Publications Inc., New York (1972).
    50. F. A. L. Dullien, Porous media fluid transport and pore structure, Academic Press, New York (1979).
    51. A. E. Scheidegger. The Physics of flow through porous media, University of Toronto Press, Great Britain (1974).
    52. S. J. Wu and L. W. Hourng, Permeability boundary condition for numerical simulation in resin transfer molding, Polymer Engineering and Science, 35,1272-1281 (1995).
    53. F. Trochu and R. Gauvin, Limitations of a boundary-fitted finite difference method for the simulation of the resin transfer molding process, Journal Of Reinforced Plastics and Composites,11, 772-786 (1992).
    54. G. P. Androutsopoulos and R. Mann, Evaluation of mercury porosimeter experiments using a network pore structure model, Chemical Engineering Science, 34, 1203-1212 (1979).
    55. M. M. Dias and A. C. Payatakes, Network models for two-phase flow in porous media: part1, immiscible microdisplacement of non-wetting fluids, J. of Fluid Mechanics, 164, 305-336 (1986).
    56. C. M. Kipphut, and R. M. German, Powder selection for shape retention in powder injection molding, Int. J. Powder Metall., 27, 117-124 (1991).
    57. C. Y. Chang, Numerical simulation of two-dimensional wick debinding in metal powder injection molding, Advanced Powder Tech., 12, 177-194 (2003).
    58. J. K. Wright and J. R. G. Evans, Removal of organic vehicle from moulded ceramic bodies by capillary action, Ceramics International, 17, 79-87 (1991).
    59. L. M. Liou, Optimum analysis of wick debinding in MIM, Master’s Thesis, Mech. Eng. Dept., National Central University, Taiwan (1999).

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