雷射積層製造不銹鋼工件機械特性分析

以作者查詢圖書館館藏

、以作者查詢臺灣博碩士

、以作者查詢全國書目

、勘誤回報

、線上人數：97

、訪客IP：3.145.9.200

姓名

沈鈴潔(Ling-Chieh Shen) 查詢紙本館藏

畢業系所

機械工程學系

論文名稱

雷射積層製造不銹鋼工件機械特性分析
(Mechanical Analysis of Laser Additive Manufacturing Builds of a Stainless Steel)

相關論文

★ 晶圓針測參數實驗與模擬分析	★ 車銑複合加工機床面結構最佳化設計
★ 精密空調冷凝器軸流風扇葉片結構分析	★ 第四代雙倍資料率同步動態隨機存取記憶體連接器應力與最佳化分析
★ PCB電性測試針盤最佳鑽孔加工條件分析	★ 鋰-鋁基及鋰-氮基複合儲氫材料之製程開發及研究
★ 合金元素(錳與鋁)與球磨處理對Mg2Ni型儲氫合金放電容量與循環壽命之影響	★ 鍶改良劑、旋壓成型及熱處理對A356鋁合金磨耗腐蝕性質之影響
★ 核電廠元件疲勞壽命模擬分析	★ 可撓式OLED封裝薄膜和ITO薄膜彎曲行為分析
★ MOCVD玻璃承載盤溫度場分析	★ 不同環境下之沃斯回火球墨鑄鐵疲勞裂縫成長行為
★ 不同環境下之Custom 450不銹鋼腐蝕疲勞性質研究	★ AISI 347不銹鋼腐蝕疲勞行為
★ 環境因素對沃斯回火球墨鑄鐵高週疲勞之影響	★ AISI 347不銹鋼在不同應力比及頻率下之腐蝕疲勞行為

檔案

[Endnote RIS 格式]

[Bibtex 格式]

[相關文章]

[文章引用]

[完整記錄]

[館藏目錄]

[檢視]

[下載]

本電子論文使用權限為同意立即開放。
已達開放權限電子全文僅授權使用者為學術研究之目的，進行個人非營利性質之檢索、閱讀、列印。
請遵守中華民國著作權法之相關規定，切勿任意重製、散佈、改作、轉貼、播送，以免觸法。

摘要(中)

雷射積層製造以雷射加熱熔融粉末之方式，將金屬粉末逐層熔於基板上，藉由層層疊加直至物件完成。本研究目的為探討使用金屬粉末進行雷射積層製造時，積層方向對積層物件各項性質之影響，選用之材料為AISI 420模具鋼。本研究使用選擇雷射熔融粉末床積層製造製作三種不同積層方向之拉伸試片，分別是沿著試片厚度方向積層的Group A試片、沿著試片寬度方向積層的Group B試片以及沿著試片長度方向積層的Group C試片。並對試片進行各項材料性質之量測，包括幾何形狀與尺寸、表面粗糙度、密度、硬度與殘留應力，同時藉由拉伸試驗求得積層試片之機械性質，最後進行破斷面及微結構觀察。此外，本研究透過有限元素模型模擬金屬粉末積層製造過程，並藉由與尺寸及殘留應力量測實驗結果比對，以驗證模擬的有效性。
　　實驗結果顯示，對於積層試片之形狀與尺寸而言，Group A與Group C試片具備良好的尺寸精度，但Group A試片有嚴重的翹曲變形發生，而Group C試片則無此現象。而表面粗糙度與密度受到積層方向之影響較小。積層方向對硬度有一定影響，Group C試片之晶粒較其他組試片小，因此該組試片的硬度最大。由殘留應力量測結果發現，最後幾層疊加的區域會有較大之殘留應力。拉伸試驗結果顯示積層方向對拉伸試片之機械性質具有很大的影響。因為積層方向會影響晶粒成長方向，所以當拉伸方向與晶粒長向平行時，試片有較大的強度。因此，Group C試片之機械性質最佳；而Group A與Group B之性質差不多，因其晶粒成長方向皆與拉伸方向垂直。此外，由破斷面之觀察發現，破裂起源於試片內部結構之介在物以及殘留張應力最大之區域。X光繞射及微結構分析顯示本研究積層製造試片之結構組成主要為麻田散鐵，並伴隨部分殘留沃斯田鐵。
　　透過與實驗量測結果比對，本研究所建立之有限元素模型確實可以有效預測積層拉伸試片之幾何尺寸及殘留應力分佈。由模擬之殘留應力分佈可以發現，積層過程中，底板的殘留應力分佈只有在製造最初幾層金屬時才會受到影響，隨著積層高度提升，底板應力受到之影響逐漸變小。殘留張應力多存在於最後幾層之積層區域中；而殘留壓應力則發生在試片中間區域。此外，隨著積層物件高度上升，沿高度方向之殘留正向應力愈大。

摘要(英)

The aim of this study is to investigate the relationship between build direction and the relevant properties of laser additive manufacturing (LAM) build of AISI 420 steel. Three build directions are considered in fabricating tensile test specimens by selective laser melting (SLM) process with a scanning pattern of alternating path. The SLM specimens are divided into three groups according to their build direction, namely Group A, Group B, and Group C. Group A is built along the thickness direction, Group B is built along the width direction, and Group C is built along the length direction. In addition, a computer-aided engineering (CAE) technique is employed to simulate the SLM process through finite element method (FEM). In order to validate the FEM model, experimental measurements of residual stress and geometry of SLM builds are carried out for comparison. Tensile properties, density, hardness, surface roughness, and microstructure are also analyzed for the given SLM builds.
　　Experimental results indicate that build direction barely affects the surface roughness and density of SLM built parts. However, it has great effects on geometry, hardness, tensile properties, and microstructure. Group A specimens have good dimensional accuracy, but buckle seriously. Group C specimens have both good dimensional and geometrical accuracy. Group B specimens have the smallest hardness as they contain the largest mean crystallite size, compared to Groups A and C. Tensile test results show that Group C has the highest yield stress, ultimate tensile stress, and elongation. Fractography analysis results reveal that fracture is initiated at either inclusion or at the region with a large tensile residual stress. Optical and scanning electron micrographs indicate that grain grows along the build direction, which influences tensile properties significantly. The loading direction in tensile test is parallel to the grain growth direction of Group C, but perpendicular to that of Groups A and B. As a result, Group C has the best tensile properties. Based on XRD results, SLM specimens contain mainly martensite and retained austenite phases.
　　FEM simulation of SLM process is performed for Group A, Group B, and Group C in various build directions. The FEM model is validated to be effective as it makes fair to good predictions of geometry and residual stress distribution. According to the residual stress distribution in numerical simulation, stress in the baseplate is only affected during the first-few-layer deposition. Tensile residual stress is generally located in the final top layers of SLM built part, and compressive residual stress exists in the middle SLM build. In addition, the residual normal stress in the build direction becomes larger as the height of SLM build increases.

關鍵字(中)

★ 雷射積層製造
★ SS420不鏽鋼
★ 機械性質

關鍵字(英)

★ Laser additive manufacturing (LAM)
★ SS420
★ Mechanical property

論文目次

LIST OF TABLES VIII
LIST OF FIGURES IX
1. INTRODUCTION 1
1.1 Laser Additive Manufacturing 1
1.2 Effects of Processing Parameters 6
1.3 Analysis of Residual Stress and Deformation by Finite Element Method 11
1.4 Purpose 13
2. EXPERIMENTAL PROCEDURES 15
2.1 Specimen Preparation by Selective Laser Melting 15
2.2 Measurement of Geometry and Surface Roughness 17
2.3 Measurement of Density and Hardness 19
2.4 Measurement of Residual Stress 21
2.5 Tensile Testing 21
2.6 Fractography and Microstructural Analysis 22
3. FINITE ELEMENT MODEL 24
3.1 Thermal and Mechanical Modeling 24
3.2 Material Properties 24
3.3 Model Description 26
4. RESULTS AND DISCUSSION 30
4.1 Experimental Results 30
4.1.1 Geometry and Surface Roughness 30
4.1.2 Density and Hardness 34
4.1.3 Residual Stress 35
4.1.4 Tensile Properties 40
4.1.5 Fractography and Microstructural Analysis 41
4.1.6 Effect of Build Direction 53
4.2 Numerical Analysis Results 55
4.3 Comparison of Numerical and Experimental Results 68
5. CONCLUSIONS 76
REFERENCES 78

參考文獻

REFERENCES
1. I. Gibson, D. W. Rosen, and B. Stucker, “Introduction and Basic Principle,” Chapter 1 in Additive Manufacturing Technologies: Rapid Prototyping to Direct Digital Manufacturing, Springer, New York, USA, 2010.
2. D. Gu, “Introduction,” Chapter 1 in Laser Additive Manufacturing of High-Performance Materials, Springer-Verlag, Berlin, Germany, 2015.
3. The Economist, A Third Industrial Revolution, http://www.economist.com/node/21552901, accessed on September 25, 2018.
4. D. Gu and B. He, “Finite Element Simulation and Experimental Investigation of Residual Stresses in Selective Laser Melted Ti–Ni Shape Memory Alloy,” Computational Materials Science, Vol. 117, pp. 221-232, 2016.
5. D. Gu, “Laser Additive Manufacturing (AM): Classification, Processing Philosophy, and Metallurgical Mechanisms,” Chapter 2 in Laser Additive Manufacturing of High-Performance Materials, Springer-Verlag, Berlin, Germany, 2015.
6. A. Simchi and H. Pohl, “Effects of Laser Sintering Processing Parameters on the Microstructure and Densification of Iron Powder,” Materials Science and Engineering: A, Vol. 359, pp. 119-128, 2003.
7. B. Dutta, S. Palaniswamy, J. Choi, L. J. Song, J. Mazumder, and FASM, “Additive Manufacturing by Direct Metal Deposition,” Advanced Materials and Processes, Vol.169, pp. 33-36, 2011.
8. M. Brandt, “Laser-aided Direct Metal Deposition of Metals and Alloys,” Chapter 1 in Laser Additive Manufacturing: Materials, Design, Technologies, and Applications, Woodhead Publishing, Cambridge, 2017.
9. S. Koric and B. G. Thomas, “Thermo-mechanical Models of Steel Solidification Based on Two Elastic Visco-plastic Constitutive Laws,” Journal of Materials Processing Technology, Vol. 197, pp. 408-418, 2008.
10. P. Mercelis and J. P. Kruth, “Residual Stresses in Selective Laser Sintering and Selective Laser Melting,” Rapid Prototyping, Vol. 12, pp. 254-265, 2006.
11. L. Parry, I. A. Ashcroft, and R. D. Wildman, “Understanding the Effect of Laser Scan Strategy on Residual Stress in Selective Laser Melting Through Thermo-mechanical Simulation,” Additive Manufacturing, Vol. 12, pp. 1-15, 2016.
12. B. Cheng, S. Shrestha, and K. Chou, “Stress and Deformation Evaluations of Scanning Strategy Effect in Selective Laser Melting,” Additive Manufacturing, Vol. 12, pp. 240-251, 2016.
13. G. Casalino, S. L. Campanelli, N. Contuzzi, and A. D. Ludovico, “Experimental Investigation and Statistical Optimization of the Selective Laser Melting Process of a Maraging Steel,” Optics & Laser Technology, Vol. 65, pp. 151-158, 2015.
14. B. Vandenbroucke and J. P. Kruth, “Selective Laser Melting of Biocompatible Metals for Rapid Manufacturing of Medical Parts,” Rapid Prototyping, Vol. 13, pp. 196-203, 2007.
15. X. Zhao, Q. Wei, B. Song, Y. Liu, X. Luo, S. Wen, and Y. Shi, “Fabrication and Characterization of AISI 420 Stainless Steel Using Selective Laser Melting,” Materials and Manufacturing Processes, Vol. 30, pp. 1283-1289, 2015.
16. K. Kempen, E. Yasa, L. Thijs, J. P. Kruth, and J. V. Humbeeck, “Microstructure and Mechanical Properties of Selective Laser Melted 18Ni-300 Steel,” Physics Procedia, Vol. 12, pp. 255-263, 2011.
17. Z. Wang, T. A. Palmer, and A. M. Beese, “Effect of Processing Parameters on Microstructure and Tensile Properties of Austenitic Stainless Steel 304L Made by Directed Energy Deposition Additive Manufacturing,” Acta Materialia, Vol. 110, pp. 226-235, 2016.
18. M. Gouge and P. Michaleris, “Microstructure and Mechanical Properties of AM Builds,” Chapter 5 in Thermo-Mechanical Modeling of Additive Manufacturing, Butterworth-Heinemann, Oxford, 2018.
19. J. Chen, L. Xue, and S-H Wang, “Experimental Studies on Process-induced Morphological Characteristics of Macro- and Microstructures in Laser Consolidated Alloys,” Journal of Materials Science, Vol. 46, pp. 5859-5875, 2011.
20. S. H. Sun, Y. Koizumi, T. Saito, K. Yamanaka, Y. P. Li, Y. Cui, and A. Chiba, “Electron Beam Additive Manufacturing of Inconel 718 Alloy Rods: Impact of Build Direction on Microstructure and High-temperature Tensile Properties,” Additive Manufacturing, Vol. 23, pp. 457-470, 2018.
21. Q. Zhang, J. Chen, Z. Zhao, H. Tan, X. Lin, and W. Huang, “Microstructure and Anisotropic Tensile Behavior of Laser Additive Manufactured TC21 Titanium Alloy,” Materials Science and Engineering: A, Vol. 673, pp. 204-212, 2016.
22. M. Kubiak, W. Piekarska, and S. Stano, “Modelling of Laser Beam Heat Source Based on Experimental Research of Yb:YAG Laser Power Distribution,” International Journal of Heat and Mass Transfer, Vol. 83, pp. 679-689, 2015.
23. A. Hussein, L. Hao, C. Yan, and R. Everson, “Finite Element Simulation of the Temperature and Stress Fields in Single Layers Built Without-support in Selective Laser Melting,” Materials and Design, Vol. 52, pp. 638-647, 2013.
24. Y. Du, X. You, F. Qiao, L. Guo, Z. Liu, “A Model for Predicting the Temperature Field During Selective Laser Melting,” Results in Physics, Vol. 12, pp. 52-60, 2019.
25. T. Amine, J. W. Newkirk, and F. Liou, “Investigation of Effect of Process Parameters on Multilayer Builds by Direct Metal Deposition,” Applied Thermal Engineering, Vol. 73, pp. 500-511, 2014.
26. E. R. Denlinger, M. Gouge, J. Irwin, and P. Michaleris, “Thermomechanical Model Development and in Situ Experimental Validation of the Laser Powder-bed Fusion Process,” Additive Manufacturing, Vol. 16, pp. 73-80, 2017.
27. C. Li, C. H. Fu, Y. B. Guo, and F. Z. Fang, “Fast Prediction and Validation of Part Distortion in Selective Laser Melting,” Procedia Manufacturing, Vol. 1, pp. 355-365, 2015.
28. K. Shah, I. U. Haq, S. A. Shah, F. U. Khan, M. T. Khan, and S. Khan, “Experimental Study of Direct Laser Deposition of Ti-6Al-4V and Inconel 718 by Using Pulsed Parameters,” The Scientific World Journal, Vol. 2014, pp. 84154901-84154906, 2014.
29. T. Mukherjee, W. Zhang, and T. DebRoy, “An Improved Prediction of Residual Stresses and Distortion in Additive Manufacturing,” Computational Materials Science, Vol. 126, pp. 360-372, 2017.
30. A. N. Isfahany, H. Saghafian, and G. Borhani, “The Effect of Heat Treatment on Mechanical Properties and Corrosion Behavior of AISI420 Martensitic Stainless Steel,” Journal of Alloys and Compounds, Vol. 509, pp. 3931-3936, 2011.
31. AZoM, Stainless Steel - Grade 420, https://www.azom.com/article.aspx?ArticleID=972, accessed on December 5, 2018.
32. MatWeb, 420 Stainless Steel, http://www.matweb.com/search/datasheettext.aspx?matguid=641544e4c9f1425390d05ae37d55440a, accessed on October 16, 2018.
33. K. R. Sriraman, S. G. S. Raman, and S. K. Seshadri, “Influence of Crystallite Size on the Hardness and Fatigue Life of Steel Samples Coated With Electrodeposited Nanocrystalline Ni–W Alloys,” Materials Letters, Vol. 61, pp. 715-718, 2007.
34. H. Bhadeshia and R. Honeycombe, “Formation of Martensite,” Chapter 5 in Steels: Microstructure and Properties, Butterworth-Heinemann, Oxford, UK, 2017.
35. N. H. van Dijk, A. M. Butt, L. Zhau, J. Sietsma, S. E. Offerman, J. P. Wright, and S. van der Zwaag, “Thermal Stability of Retained Austenite in TRIP Steels Studied by Synchrotron X-ray Diffraction During Cooling,” Acta Materialia, Vol. 53, pp. 5439-5447, 2005.
36. P. Scherrer, “Bestimmung der Grösse und der inneren Struktur von Kolloidteilchen mittels Röntgensrahlen,” Nachrichten von der Gesellschaft der Wissenschaften zu Göttingen, Vol. 1918, pp. 98-100, 1918.
37. N. Takata, R. Nishida, A. Suzuki, M. Kobashi, and M. Kato, “Crystallographic Features of Microstructure in Maraging Steel Fabricated by Selective Laser Melting,” Metals, Vol. 8, pp. 440, 2018.

指導教授

林志光(Chih-Kuang Lin)

審核日期

2019-8-24

推文