隨著生醫產品與個性化商品設計件趨於複雜與多樣性，傳統製造方法以漸趨無法滿足這些需求，積層製造為一可行的解決方案，同時可以節省材料與減輕重量，但在積層製造中常使用鏤空設計來減少重量，但在製造程中容易受到殘留應力導致翹曲變形，其中又以選擇性雷射熔融(Selective Laser Melting; SLM)積層製造最為嚴重，在SLM中使用雷射光光斑半徑約在30 μm，溫度在空間中分布極度不平均勻，而產生劇烈的SLM製程應變而導致加工失敗，所以了解殘留應力在選擇性雷射熔融積層製造中是重要的。
本論文將實驗方法與模擬方法兩者結合分析SLM製程中殘留應力與翹曲，可大量節省SLM殘留應力模擬的運算資源。藉由實驗方法找尋在SLM製程中重要的物理參數，透過單層掃描實驗與多層掃描實驗分析SLM製程應變後，將此應變帶入有限元素模型中分析殘留應力與翹曲，最終分析結果顯示SLM製程應變受到熔池幾何尺寸與雷射光跡間距的影響，考慮這兩項因素的影響，液－固相變化的應變與計算出的SLM製程應變，兩者數值相似，將此SLM製程應變帶入有限元素模型中可有效預測殘留應力與翹曲趨勢。

A key challenge in selective laser melting (SLM) addictive manufacturing is the residual stress induced cracking defects and workpiece distortion. The residual stress in the workpiece is resulted from the high thermal gradient around the laser irradiated point, the resolidification of the melted powder metal, and the inelastic constitutive behavior of the workpiece. For estimating the stress in the workpeice, numerical simulations based on coupled optical-thermomechanical theory requires significant computing time. To simplify the analysis, this thesis proposed a semi-inverse approach that first characterize a process strain experimentally and then apply it as the driving force in a subsequent numerical finite element stress model. Because the thermal effect is not considered directly in the simplified model, computational time can be reduced significantly. The proposed procedure was applied to investigate the stress and warpage of a SLM-fabricated SS316L strip. The warpage and stress trends obtained from the simulation agree to experimental measurements and literature data. From the analyses it was shown that the melt pool dimensions including the typical width and depth, and the track-to-track and layer-to-layer overlapping geometries contribute significantly to the process strain magnitude. Furthermore, the effects of SLM process parameters including the laser power and scanning speed can be considered through the melt pool geometry.

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