本研究結合雷射披覆法與選擇性雷射燒結法形成新的合成加工方法，探討加工參數對雷射燒結和雷射披覆孔隙率的影響。
在實驗上，第一部分運用選擇性雷射燒結的方式進行多孔性薄件製作，以熱感式拓印法探討雷射功率和雷射掃描速度對燒結件孔隙率的影響，第二部分運用雷射披覆法燒結件進行後續的堆疊加工，探討結合雷射披覆法與雷射選擇性燒結法的可行性，並分析雷射功率對披覆後的試件之孔隙率。在數值分析方面，以自行編寫數值分析程式，分析雷射披覆過程中因粉末溫度產生的表面能差異對孔隙率的影響，比較計算與實驗量測結果，發現具有一致性。
本研究旨在證明結合雷射披覆法與選擇性雷射燒結法加工的可行性，文中說明雷射功率引發的表面能差異將對披覆試件孔隙率造成影響，所得之實驗及數值分析結果可為後續研究之基礎。

The aim of this study is to combine the laser cladding and selective laser sintering techniques to form a new hybrid method, and investigates the effects of porosity of the forming parts numerically and experimentally.
In the experiment, the selective laser sintering technique has been applied to produce thin layers, and the surface porosity with various laser powers and scanning speeds has been characterized by thermal imprint method. Furthermore the laser cladding technique has been applied to build up the bulk clad on the thin layers and the surface porosity was also inspected.
In the numerical analysis, a computation model was developed to analyze the porosity based on the surface tension and energy of cladding powders at various temperatures. The results show a good agreement between the numerical analysis and the experimental measurement.
This novel method provides the feasibility for forming thin metal parts, and the structure properties may be improved for the porous parts directly formed by selective laser sintering.

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