由於工業發展快速，製程日新月異，若要由傳統Trial and Error方式進行製程參數改良得到所需之產品品質將耗費許多成本與人力，而產品之品質通常與其微組織有一定之關係，故本研究便採用電腦數值模擬技術去進行兩個製程之微組織模擬，分別為熱電材料之區域熔融製程與Ti-6Al-4V之選擇性雷射熔融製程。本研究分別建立兩製程之溫度場模組，經驗證後將得到之溫度場結果帶入微組織模組中模擬相對應製程之微組織，並且與實際相對應製程之產品微組織做比對、驗證。
在區域熔融部分利用與實際實驗結果之驗證找出碲化鉍之晶粒成核成長參數，並利用此參數對相關製程參數進行微組織之模擬，發現加熱環數目拆成兩個或加熱環移動度先慢後快時，晶粒會有變大之趨勢，使熱電材料之Power Factor變好。且發現長晶凝固界面與晶粒大小、柱狀晶形貌有關。當凝固界面較穩定時(平或凸面)晶粒大小會較大且有較易形成柱狀晶之趨勢。在選擇性雷射熔融部分，建立單點雷射熔融微組織模型，將模擬結果與實驗驗證找出本研究材料之晶體成核成長參數，以利進行後續之塊材與粉體之模擬。

In this study, a numerical model has been developed to simulate the variation/distribution of temperature and the subsequent microstructure of Bi2Te3 fabricated by zone-melting technique and Ti-6Al-4V fabricated by Selective Laser Melting technique.
In zone-melting part, an experiment is conducted to measure the temperature variation/distribution during the zone-melting process to validate the numerical system. The temperature variation/distribution measured by experiment is compared to the results of numerical simulation. The results show that our model and the experiment are well matched. Then the model is used to evaluate the crystal formation for Bi2Te3 of 30mm diameter process with different processing parameters. In the end, we use this model to predict the crystal formation of zone-melting process for Bi2Te3 with a 45 mm diameter. The results show that it is difficult to grow columnar crystal when the diameter comes to 45 mm.
In Ti-6Al-4V manufactured by Selective Laser Melting process part, a simplified model of single point laser heat source is established to ignore the Gaussian distribution effect of moving laser heat source. And the subsequent microstructure result of simulation is compared to the experimental results to acquire the simulation parameters of crystal growth.

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