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完整後設資料紀錄
DC 欄位 | 值 | 語言 |
---|---|---|
dc.contributor.advisor | 陳俊杉(Chuin-Shan Chen) | |
dc.contributor.author | Yi-Pin Chen | en |
dc.contributor.author | 陳義彬 | zh_TW |
dc.date.accessioned | 2021-05-17T09:14:16Z | - |
dc.date.available | 2014-08-20 | |
dc.date.available | 2021-05-17T09:14:16Z | - |
dc.date.copyright | 2012-08-20 | |
dc.date.issued | 2012 | |
dc.date.submitted | 2012-08-16 | |
dc.identifier.citation | [1] G.J. Ackland and A.P. Jones (2006), ”Applications of local crystal structure measures in experiment and simulation”, Physical Review B, Vol. 73, 54.
[2] M.F. Ashby (1970), “The deformation of plastically non-homogeneous materials”, Philosophical Magazine, Vol. 21,399. [3] M.I. Baskes (1992), “Modified embedded-atom potentials for cubic materials and impurities”, Physical Review B, Vol. 46, 5. [4] D. Christopher, R. Smith and A. Richter (2001), “Atomistic modeling of nanoindentation in iron and silver”, Nanotechnology, Vol. 12, 372. [5] F.C. Frank (1951), “Crystal dislocations—elementary concepts and definitions“, Phil. Mag. Ser., Vol. 7, 809. [6] H. Gao, Y. Huang, W.D. Nix and J.W. Hutchinson, “Mechanism-based strain gradient plasticity—I. Theory“ , Journal of the Mechanics and Physics of Solids, Vol. 47, 1239. [7] J.D. Honeycutt and H.C. Andersen (1987), “Molecular dynamics study of melting and freezing of small Lennard-Jones clusters”, Journal of Physical Chemistry, Vol. 91, 4950. [8] J. Hua and A. Hartmaier (2010), “Determining Burgers vectors and geometrically necessary dislocation densities from atomistic data“, Modelling and Simulation in Materials Science and Engineering, 18. [9] Y. Huang, X. Feng, G.M. Pharr, and K.C. Hwang (2007), “A nano-indentation model for spherical indenters“ , Modelling and Simulation in Materials Science and Engineering, Vol. 15, 255. [10] Y. Huang, F. Zhang, K.C. Hwang, W.D. Nix, G.M. Pharr and G. Feng (2006), “A model of size effects in nano-indentation“ , Journal of the Mechanics and Physics of Solids, Vol. 54, 1668. [11] E.T. Lilleodden, J.A. Zimmerman, S.M. Foiles and W.D. Nix (2002), “Atomistic simulations of elastic deformation and dislocation nucleation during nanoindentation”, Journal of the Mechanics and Physics of Solids, Vol. 51, 901. [12] J. Knap and M. Ortiz (2003), ”Effect of indenter-radius size on Au (001) nanoindentation”, Physical Review Letter, Vol. 90, 226102. [13] W.D. Nix and H. Gao (1998), “Indentation size effects in crystalline materials: a law for strain gradient plasticity“, Journal of the Mechanics and Physics of Solids, Vol. 46, 411. [14] F. Nye (1953), “Some geometrical relations in dislocated crystals“, Acta Metallurgica, Vol. 1, 153. [15] W.C. Oliver and G.M. Pharr (1992), “An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments”, Journal of Materials Research, Vol. 7, 1564. [16] S. Plimpton, A. Thompson and P. Crozier, “LAMMPS Molecular Dynamics Simulator”, http://lammps.sandia.gov/. [17] A. Stukowski and K. Albe (2010), “Extracting dislocations and non-dislocation crystal defects from atomistic simulation data”, Modelling and Simulation in Materials Science and Engineering, Vol. 18, 085001. [18] J. Shewchuk, “Triangle”, http://www.cs.cmu.edu/~quake/triangle.html. [19] J.G. Swadener, E.P. George and G.M. Pharr (2002), “The correlation of the indentation size effect measured with indenters of various shapes”, Journal of the Mechanics and Physics of Solids, Vol. 50, 681. [20] G.I. Taylor (1934), ”The formation of emulsions in definable fields of flow”, Proceedings the royal of society, Vol. 11, 2196. [21] J.A. Zimmerman, C.L. Kelchner, P.A. Klein, J.C. Hamilton and S.M. Foiles (2001), ”Surface step effects on nanoindentation”, Physical Review Letter, Vol. 87, 165507. [22] J.A. Zimmerman, E. B. WebbIII, J.J. Hoyt, R.E. Jones, P.A. Klein and D.J. Bammann (2004), “Calculation of stress in atomistic simulation”, Modelling and Simulation in Materials Science and Engineering, Vol. 12, 319. [23] 賴家偉(2006), “以分子動力模擬探討奈米壓痕之變形行為與差排機制”, 國立台灣大學碩士論文. [24] 詹志陽(2011), “以原子尺度模擬探討奈米壓痕之尺寸效應”, 國立台灣大學碩士論文. | |
dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/6506 | - |
dc.description.abstract | 奈米壓痕為微觀及奈米尺度中最為普遍之材料強度檢測法。其力學性質隨量測尺度變化而有所改變,與一般連體材料並不相同,被稱之為壓痕尺寸效應。Nix and Gao以幾何必要差排密度補足應變之幾何不相容,提出應變梯度塑性理論解釋尺寸效應。對於微小奈米尺度實驗有技術上之困難性,以原子尺度模擬探討尺寸效應與幾何必要差排密度為重要之可行之策。
本研究使用半徑20A至100A球形壓痕探針及角錐形壓痕探針檢測FCC單晶鎳之奈米薄膜。由原子模擬資訊直接計算硬度,分別與壓痕探針半徑平方根及壓痕深度平方根成反比,成果吻合於應變梯度塑性理論。 為計算幾何必要差排密度,以理論模型之等效塑性區進行擷取差排,各尺寸球形壓痕探針及角錐形壓痕探針所計算出之幾何必要差排密度分別與Swadener等人及Nix&Gao之理論模型相吻合。本研究之硬度與幾何必要差排密度皆符合理論推導,成功驗證奈米尺度下應變梯度塑性理論與幾何必要差排密度尺寸效應。 | zh_TW |
dc.description.abstract | Nanoindentaiton is the most useful test method to probe the strength of materials that are manufactured at micro or nano scales. Unlike the continuum behavior, the mechanical properties exhibit a strong dependency with characteristic length scale, which is also referring to the nanoindentation size effect. Nix and Gao proposed the strain gradient plasticity theory to interpret the size effect by introducing a geometrically necessary dislocation density to overcome the strain incompatibility. Atomistic simulations were conducted to elucidate the relationship between size effect and the geometrically necessary dislocation density in this study.
In this study, spherical indenters with their radius from 20A to 100A and Berkovich indenter were exploited to examine the FCC single crystal thin firm of Nickel. Hardness was directly obtained from the atomistic simulation that hardness is inversely proportion to the square root of indenter radius and indentation depth respectively. The findings agree with the well-known strain gradient theory. In order to calculate the geometry necessary dislocation density, an equivalent plastic zone size was chose to meet the theoretic requirement. In present work, diverse radius of spherical indenter and Berkovich indenter indicated that the geometry necessary dislocation density showed a great agreement with the theory proposed by Swadener et al and Nix&Gao respectively. The hardness and geometric necessary dislocation density extracted directly from atomistic simulation were both agreed with the theory. It can be concluded that the strain gradient plasticity of size effect and geometric necessary dislocation density were valid at atomistic scale. | en |
dc.description.provenance | Made available in DSpace on 2021-05-17T09:14:16Z (GMT). No. of bitstreams: 1 ntu-101-R99521604-1.pdf: 3529844 bytes, checksum: 5f80ff32518902d5b626153d8a56f8a6 (MD5) Previous issue date: 2012 | en |
dc.description.tableofcontents | 口試委員審定書…………………………………………………………...#
致謝………………………………………………………………………...# 中文摘要 1 ABSTRACT 2 目錄 4 圖片目錄 6 第一章 緒論 9 1.1 研究背景與動機 9 1.2 研究目的 11 1.3 論文架構 11 第二章 文獻回顧與理論方法 13 2.1 微米尺度理論方法 13 2.2 原子尺度模擬幾何必要差排擷取 17 第三章 模擬研究方法 20 3.1 分子動力方法 20 3.2 壓痕探針勢能 21 3.3 系統平衡態 23 3.4 硬度計算 23 3.5 差排擷取 25 3.6 塑性區差排密度 27 第四章 模擬實作 29 4.1 模擬實作軟體 29 4.2 模擬環境設置 29 4.3 實作模擬流程 31 4.3.1 壓痕流程 31 4.3.2 模擬資訊擷取 32 第五章 結果與討論 38 5.1 壓痕之差排滑移 38 5.2 差排與量測硬度變化 40 5.3 邊界與試體尺寸 42 5.4 尺寸效應成果-球形壓痕探針 44 5.5 尺寸效應成果-角錐形壓痕探針 53 第六章 結論與展望 56 6.1 總結 56 6.2 未來展望 57 參考文獻 58 | |
dc.language.iso | zh-TW | |
dc.title | 以原子尺度模擬探討幾何必要差排與壓痕探針之尺寸效應 | zh_TW |
dc.title | Investigation of Geometric Necessary Dislocation and Indenter Size Effect Using Atomistic Simulation | en |
dc.type | Thesis | |
dc.date.schoolyear | 100-2 | |
dc.description.degree | 碩士 | |
dc.contributor.oralexamcommittee | 敖仲寧(Jon-Ning Aoh),張怡玲(I-Ling Chang) | |
dc.subject.keyword | 壓痕尺寸效應,應變梯度塑性理論,幾何必要差排, | zh_TW |
dc.subject.keyword | Nano indentation size effect,Strain gradient plasticity,Geometrically necessary dislocation density, | en |
dc.relation.page | 60 | |
dc.rights.note | 同意授權(全球公開) | |
dc.date.accepted | 2012-08-16 | |
dc.contributor.author-college | 工學院 | zh_TW |
dc.contributor.author-dept | 土木工程學研究所 | zh_TW |
顯示於系所單位: | 土木工程學系 |
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