積層製造為近年來逐漸興起的新型加工方法，有別於舊式將材料除去的減法加工，其是透過一體成型的方式，直接將產品一層一層地製作出來，這種加工方式可以用來製造幾何形狀極為複雜的特殊零件，也可使新型產品在設計以及開發上更加靈活便利。選擇性雷射熔融(SLM)是一種金屬積層製造技術，其加工原理為，利用高能量雷射熱源使金屬粉末熔化後凝固成加工層，並重複鋪粉及燒熔的程序將工件一層一層地製造出來。而其最大的問題在於，材料在製程中會因為雷射燒熔產生高溫度梯度，進而引發熱殘留應力，使得成品常會有翹曲等變形缺陷。有鑑於此，本研究針對SLM製程成品之翹曲變形部分，發展一套翹曲預測方法，先由逆向分析方法得到SLM製程應變，並將之用於等效數值模擬中，基於對效率的追求，先後建立兩種模型模擬製程，同時設計不同試件執行製程實驗，驗證數值模擬之準確性，亦透過實驗結果得到優化之製程參數。其中翹曲變形之實驗和模擬結果達到良好的驗證，兩種數值模擬的模型分別在準度及效率上達到一定的成效。透過本研究所提供之模擬方法以及參數結果，讓使用者可以在實際執行製程前，即先有效率地預測變形結果以掌控製程情況，進而調整設計或做更進一步的應用，使SLM加工法在設計及製造上更趨成熟穩定。

Additive manufacturing (AM) is a form of rapid-prototyping fabrication. It enables manufacturing products of complex geometry in a layer-by-layer process directly. Among the AM processes, selective laser melting (SLM) is a promising technology for fabricating metallic workpieces. A key challenge in SLM technology is the warpage of the workpiece due to high residual stress. This thesis proposes a numerical prediction procedure for considering the warpage. The SLM process strain for SS316L was characterized experimentally, and used as an equivalent strain in the simplified finite element (FE) simulation. Two types of numerical models were constructed for efficient prediction of the workpiece warpage, and were validated by experimental measurements. The warpage values obtained from the simulations and experiments are in good agreements, and a set of optimized model parameters were obtained from SLM experiments. The methodology proposed in this thesis can also be implemented for different combinations of SLM machine and metal powder to allow fast prediction of SLM workpiece distortion and establishing mitigation plans.

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