本論文主要分成兩大主軸，分別為”模擬技術的建構”以及”應力模擬應用於積層製造”。
模擬技術的建構包含不同圓孔的鋁合金試片品的拉伸試驗、不同孔洞單元堆疊成的圓柱模型與各式人工下顎模擬模組等，利用有限元素分析軟體進行各項模擬參數與邊界條件的搭配，例如材料區塊界線，施力的固定約束、邊界附載與接觸試驗的接觸對偶、來源及目的邊界，移動端的輔助掃描、Range Function等等，最終找出不同模型各自最有效率的模擬條件。
應力模擬應用於積層製造則又分為：1. 針對不同孔洞結構與堆疊方式(#1、#2)的模型進行的壓縮模擬，探討孔洞結構、彈性模數與相對密度間的關係。2. 對於生醫用植入材應用於人體下顎進行的咬合受力模擬，討論植入材或手術導板在人體下顎不同位置時所需要面對的問題。.
實驗結果首先先藉由含圓孔之鋁合金試片的拉伸試驗來與模擬結果比較以驗證模擬技術的可信度，其兩者數據間的差異成線性關係，最低的1孔試片誤差約4 %。
將6種不同孔隙率的孔洞單元，以”口字堆疊”，”ㄇ字堆疊”兩種方法建立成不同的圓柱型模型。堆疊後的圓柱模型應力集中從原本單一孔洞集中在支柱周遭轉移到了支柱中間，改變了了力傳遞的路徑。而兩種結構中，明顯以”口字堆疊”的方式較為穩定，在趨勢上的表現也較為一致；”ㄇ字堆疊”的方式則是因為重複單元較多而接結構較為鬆散，在相同應力下能擁有較大的變形量，即較低的彈性模數。
兩者的堆疊方式皆會比實際實驗的彈性模數較高，因此額外建立一含有小孔洞的圓柱模型，其而外添加了1.42 %孔隙率使彈性模數下降了約8.1 %的幅度。同時，以相同孔隙率孔洞單元堆疊起來的兩種模型，在模擬結果中皆不會有高於材料降伏強度的應力集中值出現，因此推測在EBM試片中會有包含足以影響其機械性質的孔隙存在。
在實際應用端，藉由模擬技術來模擬人工下顎在不同區帶的表現，依序建立了普通下顎模型、齒模(toothless)模型、手術導板(Surgical Guide)模型與含有取代塊之下顎模型來依照不同需求進行模擬。主要觀察各模型在不同條件下的應力分布或應力集中的位置、探討應力遮蔽效應對植入材及周遭骨骼帶來的影響。能藉由這些模擬來預防植入材在使用的變形，同時提供做為臨床上參考的依據。
本研究透過模擬技術來分析一般難以實際進行的實驗，在工程上提升效率與節省成本，藉由應力分結果預測材料可能產生破壞或變形的位置等為優勢，期望日後能探討出孔隙率與彈性模數間的關係，並以此為依據將不同孔洞結構匯入於生醫植入材中來改善植入材的彈性模數，在降減緩應力遮蔽效應與維持機械強度間取得最佳的平衡。

關鍵字: 積層製造、有限元素分析、Ti-6Al-4V、彈性模數、孔洞結構、生醫植入材、應力遮蔽效應、人工下顎

This paper was divided into two major parst: "construction of simulation technology" and "stress simulation applied to additive manufacturing".
The first part includes the tensile test of aluminum specimens with different round holes, the cylindrical model formed by stacking different units, and various artificial mandible simulation models.
The second part is further divided into: 1. Compression simulation of different pore structures and stacking patterns (#1, #2), and then the discussion of the Gibson & Ashby relationship. 2. The simulation of the occlusal force applied to mandible, and the problems that the implant or the surgical guide should face in different positions are discussed.
The reliability of simulation results is verified by the tensile test of the aluminum specimens with round holes. The tendency between the two data is linear, and the lowest deviation in one-pore samples is about 4%. Six kinds of different porosity were built into different cylindrical models by two methods:“ㄇ-stacking (#1)”and“口-stacking (#2). The way of #2 is obviously stable and predictable; the way of #1 has larger amount of deformation and lower modulus because of the more repeating unit.
EBM samples is supposed to have plenty of unexpected self-contained porosity. When additional 1.42 % porosity was be added, 8.1 % Young's modulus value will be lower in #2 cylindrical models.
On the practical side, simulation techniques are used to simulate the performance of artificial mandible in different regions. Simple-mandible model is the most suitable model and meanwhile achieved the best balance between simulation feasibility and actual demands.
It is expected that the position may be destroyed or deformed by the stress distribution simulation result, and the relationship between the porosity and the elastic modulus in the future. At the same time, it reaches the best balance between reducing the stress shielding effect and maintaining the mechanical strength.

Keywords: additive manufacturing, porous structures, finite element analysis, Ti-6Al-4V, biomedical implant, stress shadowing effect, Young’s modulus.

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