金屬3D列印一直被視為3D列印產業最先進的技術之一，金屬3D列印能夠應用的產業最為廣泛，對於產業所帶來的助益也是一般3D列印難以比擬的。金屬3D列印技術主要包括選擇性雷射燒結(Selective Laser Sintering)以及選擇性雷射熔化(Selective Laser Melting)，此類技術是把成型用的材料（通常是顆粒或粉末）鋪在平台上，在二維(x-y)平面利用高能量的雷射照射在欲成型的位置上，使材料熔融聚合，在不同高(或深)度(z軸)重複這個步驟，就可製作出成品。牽涉到高能雷射以及精密的自動化的機台設備，金屬3D列印設備動輒數十萬美金，不但實驗門檻高，材料等消耗品也是費用不貲。本文針對SLM加工利用COMSOL軟體建立一套模擬模型。COMSOL為一套求解工程問題常用的軟體，據有自由定義的數學方程式模組，以及多物理量的耦合機制；以COMSOL為工具，將古典熱傳方程式以及輻射熱傳耦合，依據不同材料性質(密度、比熱等)、雷射參數(功率、頻率等)輸入，獲得最佳化加工參數，做為真實SLM加工依據。

Metal 3D printing has been considered as one of the most advanced technology in 3D printing. It can be applied to most industry and brings most benefit for 3D printing market. The main technologies of Metal 3D printing include selective laser sintering(SLS) and se-lective laser melting(SLM). Both above of technologies are the same concept. First, make the materials,such as powders, be laid on the platform(xy-plane). Second, focus on the po-sition we want to form by high-energy laser and make the materials be melted and fusion. Final, repeat the above two step on different platform(z-axis) to get the products. The high-energy laser equipments for 3D printing are too expensive to do experiment. This arti-cle bulit a simulation model for SLM of 3D printing by COMSOL. COMSOL is a com-monly used software to solve engineering problems with user defined PDE and mutiphys-ics couplied. Couple heat conduction and radiative heat transfer by COMSOL and obtain an optimal processing parameters according to the different material properties (density, specific heat, etc.), laser parameters (power, frequency, etc.) inputted.

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