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系統識別號 U0026-0104201820333000
論文名稱(中文) 雷射積層熔融製程之表面形貌與熔池行為數值模擬和實驗驗證
論文名稱(英文) Numerical Modeling of Surface Morphology and Melt Pool Behavior in Selective Laser Melting and Experimental Validation
校院名稱 成功大學
系所名稱(中) 材料科學及工程學系
系所名稱(英) Department of Materials Science and Engineering
學年度 106
學期 2
出版年 107
研究生(中文) 吳育哲
研究生(英文) Yu-Che Wu
學號 N58021010
學位類別 博士
語文別 中文
論文頁數 115頁
口試委員 指導教授-李旺龍
共同指導教授-林惠娟
口試委員-陳引幹
口試委員-郭瑞昭
口試委員-許志雄
口試委員-洪廷甫
中文關鍵字 選擇性雷射熔融  表面形貌  熔池行為  數值模擬  離散元素法 
英文關鍵字 Selective laser melting  surface morphology  melt-pool behavior  simulation  Discrete element method 
學科別分類
中文摘要 本研究主要藉由數值模擬的方式探討選擇性雷射熔融製程(Selective Laser Melting,SLM)中熔池行為對表面形貌的影響。為了實現並計算金屬粉末受雷射加熱後的物理現象,該模型必須考慮三維空間下的亂序粉床排列、雷射加熱、熱傳模型、材料相變化和流體流動等。其中,在表面形貌的計算是採用流體體積法(Volume of Fluid,VOF)作為自由液面的處理方式。所有的數學方程式皆是利用商用數值模擬軟體FLOW-3D進行差分化計算得到。
在製程參數探討的部分,模擬結果顯示當增加掃描速度時,表面形貌會隨之變平坦,但當掃描速度超過1150 mm/s時,表面又再次轉為粗糙。而當雷射功率提高時,表面形貌則是逐漸變粗糙,其原因可以從熔池體積和熔池壽命兩者與表面形貌的關係說明。因此,透過參數實驗發現在低熔池體積和適當的熔池壽命下,便可以獲得良好的SLM表面品質。
另外,本研究也透過一組對照模型說明在SLM模擬中考慮keyhole現象和亂序粉床的重要性,亦可從模擬結果得知當發生鑰孔(keyhole)熱傳時,熔池凝固過程因為馬蘭哥尼效應(Marangoni Effect)造成的的表面形貌變化。以上的模擬結果都有相對應的實驗驗證,也都得到很好的相似性。因此,該數值模型也能被用來作為一個SLM表面形貌預測及製程參數優化模型。
英文摘要 A three dimensional selective laser melting process simulation is developed to investigate (1) the influence of normalized process parameters on surface morphology and (2) the melt-pool behavior of a randomly-distributed powder bed with keyhole formation by Nd-YAG laser. Results showed that when the scanning speed was increased, the surface morphology initially became flatter, but then roughness developed again at high speed case. Further, as the laser power was increased, the surface morphology gradually roughened. To better describe the surface morphology phenomenon according to different laser parameters, the melt pool volume and melt pool lifetime were also investigated. With these two factors constrained, a fine surface could be obtained with a low melt pool volume and proper lifetime (approximately 100 µs to 130 µs). Also, to show the importance of evaporation during laser melting, the melt-pool temperature, melt-pool dimensions and the surface morphology are used as metrics for comparison. Through simulation, the transition from keyhole formation to the final convex surface at a local area was discovered. The simulation results are all validated via good agreement with the experiment.
論文目次 摘要 I
Extended abstract III
誌謝 XII
目錄 XIII
圖目錄 XVI
表目錄 XX
第一章 緒論 1
1-1 積層製造 1
1-2 選擇性雷射熔融 4
1-3 研究目的與動機 9
第二章 文獻回顧 10
第三章 理論基礎 18
3-1控制方程式 21
3-2自由表面處理 22
3-3表面張力的處理 27
3-4 反衝壓力 27
3-5 雷射熱源 28
3-6 粉床堆疊與排列 28
3-7邊界條件 31
3-8數值分析 31
3-8-1 GMRES 法 32
3-8-2系統分割與變數設置 32
3-9 材料性質 35
第四章 結果與討論 39
4-1表面形貌與參數探討 39
4-1-1 模型建立 39
4-1-2模型驗證 41
4-1-3表面形貌與熔池體積之探討 52
4-1-4表面形貌與熔池壽命之探討 57
4-1-5 熔池速度場對表面形貌之影響 59
4-2 多粒徑粉床與鑰孔現象 61
4-2-1 模型建立 61
4-2-2多粒徑粉床模型驗證 64
4-2-3 雷射熔融模型驗證 67
4-2-4 雷射熔融過程中keyhole現象對熔池行為的影響 74
4-3 雷射積層熔融之製程參數選擇應用 81
4-3-1 模型建立 81
4-3-2 模型應用之雷射功率選擇 85
4-3-3 模型應用之掃描線偏位選擇 95
4-3-4 雷射面掃描與多層粉床探討 98
第五章 結論 106
建議未來研究方向 108
參考文獻 109
附錄 113
參考文獻 1. 邱琬雯, 積層製造產品化技術關鍵. 2017; Available from: https://www.moea.gov.tw/MNS/doit/industrytech/IndustryTech.aspx?menu_id=13545&it_id=101.
2. Gu, D.D., Meiners, W., Wissenbach, K., and Poprawe, R., Laser additive manufacturing of metallic components: materials, processes and mechanisms. International Materials Reviews, 57(3): p. 133-164, 2012.
3. Kruth, J.P., Levy, G., Klocke, F. and Childs, T.H.C., Consolidation phenomena in laser and powder-bed based layered manufacturing. CIRP Annals - Manufacturing Technology, 56(2): p. 730-759, 2007.
4. Zhang, B., Dembinski, L. and Coddet, C., The study of the laser parameters and environment variables effect on mechanical properties of high compact parts elaborated by selective laser melting 316L powder. Materials Science and Engineering: A, 584: p. 21-31, 2013.
5. Zhang, B., Liao, H. and Coddet, C., Effects of processing parameters on properties of selective laser melting Mg–9%Al powder mixture. Materials & Design, 34: p. 753-758, 2012.
6. ASTM International, Standard Terminology for Additive Manufacturing Technologies. 2012: West Conshohocken, PA.
7. EOS, General functional principle of laser-sintering. Available from: https://www.eos.info/additive_manufacturing/for_technology_interested.
8. Buchbinder, D., Schleifenbaum, H., Heidrich, S., Meiners, W. and Bültmann, J., High Power Selective Laser Melting (HP SLM) of Aluminum Parts. Physics Procedia, 12: p. 271-278, 2011.
9. Kruth, J.P., Mercelis, P., Vaerenbergh, J.V., Froyen, L. and Rombouts, M., Binding mechanisms in selective laser sintering and selective laser melting. Rapid Prototyping Journal, 11(1): p. 26-36, 2005.
10. Kumar, S.S., Bai, V.S. and Rajasekharan, T., Aluminium matrix composites by pressureless infiltration: the metallurgical and physical properties. Journal of Physics D: Applied Physics, 41(10): p. 105403, 2008.
11. additively.com, Laser Melting (LM). Available from: https://www.additively.com/en/learn-about/laser-melting.
12. ENCYCLOPEDIA OF ENGINEERING, Atomization / Powder Metallurgy. Available from: http://www.mechscience.com/atomization-powder-metallurgy/.
13. Dai, K. and Shaw, L., Finite element analysis of the effect of volume shrinkage during laser densification. Acta Materialia, 53(18): p. 4743-4754, 2005.
14. Jamshidinia, M., Kong, F. and Kovacevic, R., Numerical Modeling of Heat Distribution in the Electron Beam Melting® of Ti-6Al-4V. Journal of Manufacturing Science and Engineering, 135(6): p. 061010-061010-061014, 2013.
15. Gürtler, F.J., Karg, M., Leitz, K.H. and Schmidt, M., Simulation of Laser Beam Melting of Steel Powders using the Three-Dimensional Volume of Fluid Method. Physics Procedia, 41: p. 881-886, 2013.
16. Yadroitsev, I., Bertrand, P. and Smurov, I., Parametric analysis of the selective laser melting process. Applied Surface Science, 253(19): p. 8064-8069, 2007.
17. Dai, D. and Gu, D., Tailoring surface quality through mass and momentum transfer modeling using a volume of fluid method in selective laser melting of TiC/AlSi10Mg powder. International Journal of Machine Tools and Manufacture, 88: p. 95-107, 2015.
18. Li, Y. and Gu, D., Parametric analysis of thermal behavior during selective laser melting additive manufacturing of aluminum alloy powder. Materials & Design, 63: p. 856-867, 2014.
19. Fabbro, R., Melt pool and keyhole behaviour analysis for deep penetration laser welding. Journal of Physics D: Applied Physics, 43(44): p. 445501, 2010.
20. Yang, J., Han, J., Yu, H., Yin, J., Gao, M., Wang, Z. and Zeng, X., Role of molten pool mode on formability, microstructure and mechanical properties of selective laser melted Ti-6Al-4V alloy. Materials & Design, 110: p. 558-570, 2016.
21. Khairallah, S.A. and Anderson, A., Mesoscopic simulation model of selective laser melting of stainless steel powder. Journal of Materials Processing Technology, 214(11): p. 2627-2636, 2014.
22. King, W.E., Barth, H.D., Castillo, V.M., Gallegos, G.F., Gibbs, J.W., Hahn, D.E., Kamath, C. and Rubenchik, A.M., Observation of keyhole-mode laser melting in laser powder-bed fusion additive manufacturing. Journal of Materials Processing Technology, 214(12): p. 2915-2925, 2014.
23. Verhaeghe, F., Craeghs, T., Heulens, J. and Pandelaers, L., A pragmatic model for selective laser melting with evaporation. Acta Materialia, 57(20): p. 6006-6012, 2009.
24. Bauereiß, A., Scharowsky, T. and Körner, C., Defect generation and propagation mechanism during additive manufacturing by selective beam melting. Journal of Materials Processing Technology, 214(11): p. 2522-2528, 2014.
25. Simonelli, M., Tuck, C., Aboulkhair, N.T., Maskery, I., Ashcroft, I., Wildman, R.D. and Hague, R., A Study on the Laser Spatter and the Oxidation Reactions During Selective Laser Melting of 316L Stainless Steel, Al-Si10-Mg, and Ti-6Al-4V. Metallurgical and Materials Transactions A, 46(9): p. 3842-385, 2015.
26. Thijs, L., Kempen, K., Kruth, J.P. and Van, J., Humbeeck, Fine-structured aluminium products with controllable texture by selective laser melting of pre-alloyed AlSi10Mg powder. Acta Materialia, 61(5): p. 1809-1819, 2013.
27. Aboulkhair, N.T., Maskery, I., Tuck, C., Ashcroft, I. and Everitt, N.M., On the formation of AlSi10Mg single tracks and layers in selective laser melting: Microstructure and nano-mechanical properties. Journal of Materials Processing Technology, 230: p. 88-98, 2016.
28. Lu, Y., Wu, S., Gan, Y., Huang, T., Yang, C., Junjie, L. and Lin, J., Study on the microstructure, mechanical property and residual stress of SLM Inconel-718 alloy manufactured by differing island scanning strategy. Optics & Laser Technology, 75: p. 197-206, 2015.
29. Yu, G.Q., , Gu, D.D., Dai. D.H., Xia, M.J., Ma, C.L. and Shi, Q.M., On the role of processing parameters in thermal behavior, surface morphology and accuracy during laser 3D printing of aluminum alloy. Journal of Physics D: Applied Physics, 49(13): p. 135501, 2016.
30. Yuan, P.P. and Gu. D.D., Molten pool behaviour and its physical mechanism during selective laser melting of TiC/AlSi10Mg nanocomposites: simulation and experiments. Journal of Physics D: Applied Physics, 48(3): p. 035303, 2015.
31. Körner, C., Bauereiß, A. and Attar, E., Fundamental consolidation mechanisms during selective beam melting of powders. Modelling and Simulation in Materials Science and Engineering, 21(8): p. 085011, 2013.
32. Lee, Y.S. and Zhang, W., Mesoscopic simulation of heat transfer and fluid flow in laser Powder bed additive manufacturing, in International Solid Freeform Fabrication Symposium. Austin. p. 1154-1165, 2015
33. Hirt, C.W. and Nichols, B.D., Volume of fluid (VOF) method for the dynamics of free boundaries. Journal of Computational Physics, 1981. 39(1): p. 201-225.
34. Noh, W.F. and Woodward, P., SLIC (Simple Line Interface Calculation). Berlin, Heidelberg: Springer Berlin Heidelberg, 1976.
35. Youngs, D.L., Time-dependent multi-material flow with large fluid distortion. In Numerical methods for fluid dynamics, Morton, K.W., Baines, M.J., Eds., Academic Press: Cambridge, MA, USA, p.273-285, 1982.
36. Raessi, M., Mostaghimi, J. and Bussmann, M., Advecting normal vectors: A new method for calculating interface normals and curvatures when modeling two-phase flows. Journal of Computational Physics, 226(1): p. 774-797, 2007.
37. De Schepper, S.C.K., Heynderickx, G.J. and Marin, G.B., CFD modeling of all gas–liquid and vapor–liquid flow regimes predicted by the Baker chart. Chemical Engineering Journal, 138(1): p. 349-357, 2008.
38. Brackbill, J.U., Kothe, D.B. and Zemach, C., A continuum method for modeling surface tension. Journal of Computational Physics, 100(2): p. 335-354, 1992.
39. Cho, J.H. and Na, S.J., Three-Dimensional Analysis of Molten Pool in GMA-Laser Hybrid Welding. Welding Journal, 88: p. 35-43, 2009.
40. Anisimov, S.I. and Khokhlov, V.A., Instabilities in laser-matter interaction. CRC press, 1995.
41. Roberts, I.A., Wang, C.J., Esterlein, R., Stanford, M. and Mynors, D.J., A three-dimensional finite element analysis of the temperature field during laser melting of metal powders in additive layer manufacturing. International Journal of Machine Tools and Manufacture, 49(12): p. 916-923, 2009.
42. Hussein, A., Hao, L., Yan, C. and Everson, R., Finite element simulation of the temperature and stress fields in single layers built without-support in selective laser melting. Materials & Design, 52: p. 638-647, 2013.
43. Saad, Y. and Schultz, M.H., GMRES: A generalized minimal residual algorithm for solving nonsymmetric linear systems. SIAM Journal on scientific and statistical computing, 7(3): p. 856-869, 1986.
44. Generalized minimal residual method. ; Available from: http://www.wikiwand.com/en/Generalized_minimal_residual_method
45. FLOW Science, FLOE-3D Documentation. 2014: FLOW Science, Inc.
46. Mills, K.C., Ti: Ti-6 Al-4 V (IMI 318), in Recommended Values of Thermophysical Properties for Selected Commercial Alloys. Woodhead Publishing. p. 211-217, 2002.
47. Tang, L. and Landers, R.G., Melt Pool Temperature Control for Laser Metal Deposition Processes—Part I: Online Temperature Control. Journal of Manufacturing Science and Engineering, 132(1): p. 011010-011010-011019, 2010.
48. Ma, C., Chen, L., Xu, J., Zhao, J. and Li, X., Control of fluid dynamics by nanoparticles in laser melting. Journal of Applied Physics, 117(11): p. 114901, 2015.
49. Wu, Y.C., Hwang, W.S., San, C.H., Chang, C.H., and Lin, H.J., Parametric study of surface morphology for selective laser melting on Ti6Al4V powder bed with numerical and experimental methods. International Journal of Material Forming, DOI: https://doi.org/10.1007/s12289-017-1391-2, 2017.
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