有鑑於科技隨時代之演進，為了因應半導體產業、熔煉工業的進步，必須使用高強度、高純度、物理穩定性高的材料。因此為了得到高品質的材料，熔煉過程中的金屬熔池溫度量測與控制成為重要的一環。
本文利用數值模擬的方式，模擬真空電子束熔煉高純度鈷金屬，探討不同總熱傳係數、電子束半徑、電子束功率之下的熔池溫度、形狀、馬蘭戈尼效應所帶動的表面流動及內部流場流動。模擬之結果並與實驗量測之冷卻水相關數據，計算出邊界之總熱傳係數及透過測溫平板上之熱平衡方程式，進而推算純鈷金屬之表面溫度，進行比較與驗證。
固定電子束半徑、能量，提高總熱傳係數時，熔池的寬度跟深度有明顯減小的趨勢。但是熔池寬度與深度減少的趨勢越來越小，表示總熱傳係數所帶走能量有限，對金屬熔池整體影響的程度有一定的限制。
固定電子束半徑，增加電子束能量，因為單位能量密度增加，使得熔池溫度提高、熔池形狀變大，這兩者都會使表面之蒸發熱損失以及輻射熱損失提高，導致能量浪費。
固定電子束能量，電子束半徑越小，單位能量密度越高，表面溫度梯度提高，造成馬蘭戈尼效應越強烈，並且會有局部過熱問題，導致蒸發熱損失提高，為了避免局部過熱，可以增加電子束半徑，降低熔池表面溫度，並且減少蒸發質量的損失。

In view of the evolution of science and technology with times and in response to the progress of semiconductor and smelting industries, it must use high-strength, high-purity, high physical stability of the material. Therefore, in order to obtain high-quality materials, molten pool temperature measurement and control becomes important issue in melting process. In this study, numerical approach is used to simulate vacuum electron beam melting high purity cobalt metal and investigate the flow and heat transfer characteristics of the molten pool. This model also considers the coupled effects of buoyancy and Marangoni forces, radiation, and evaporation losses. The results of the simulation are compare and verified with the overall heat transfer coefficient which is derived from the experimental data of the cooling water, and the surface temperature of the pure cobalt metal which is measured by plate thermometer. The results show that the width and depth of molten pool significantly decreases with increasing overall heat transfer coefficient. Increasing the electron beam power will cause the molten pool to have higher temperature and larger shape, which both result in higher evaporation heat loss and radiation heat loss. Decreasing the electron beam radius, the molten pool surface temperature gradient will increase and cause overheating problem in the center. Therefore, larger beam radius can produce larger molten pool surface area, efficiently avoid overheating, and effectively decrease evaporation loss of the base material.

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