近年來積層製造的發展性愈來愈受到重視，使用不同材料進行積層製造的可行性也受到廣泛的研究，在金屬材料的積層製造中，以金屬粉末為原料的製程已經有較成熟的發展，而若是以金屬線材為積層材料，相比金屬粉末具有更好的材料使用率、較高的沉積速率及金屬線材更易獲得等優點，使線材製程在成本考量上具有競爭力。在金屬積層製造的製程中，若能了解它的沉積機制及使用的參數對沉積結果的影響，操作員即可藉由參數的調整達到需要的產品幾何尺寸。本研究以光纖雷射的雙光模組作為能量源，使用直接能量沉積(Directed Energy Deposition, DED)的技術，探討以直徑0.8 mm的316L不鏽鋼線材垂直送線至S45C板材上的沉積情形，分別以雷射點位置、雷射能量及床台進給為實驗參數，並測量沉積物的幾何尺寸以研究參數與沉積結果之關係，並根據結果設計多層沉積實驗，測量沉積後的硬度值及以熱影像儀觀察沉積過程的溫度變化。
由實驗結果發現沉積方向雷射主要在基板上製造熔池，而遠離沉積方向雷射則是將線材加熱附著於基板上；使用較高的雷射能量會產生較高的沉積寬度，而降低床台進給則會使沉積高度提升；在硬度值的量測中發現在第一層的熔池處由於散熱能力快速，具有最高的硬度值，自第三層之後則會較穩定的維持在185 HV；以375Watt能量能夠使層與層間穩定的結合，得到薄壁結構。

In recent years, additive manufacturing has developed rapidly, and the feasibility of using different materials for additive manufacturing has also been widely studied. In the form of metal material, the process of using metal powder is mature. Compared to the metal powder materials, metal wire take advantages of material utilization, higher deposition rate, and low cost due to drawing process. In the process of metal additive manufacturing, if we can understand the deposition mechanism and the relationship between the experimental parameters and the products, the operators can adjust the parameters to achieve the desired geometry. This research mainly discusses the deposition mechanism. Single-layer and the multi-layer deposition of 316L stainless steel were studied using the direct energy deposition technology to feed the wire into the molten pool and deposit it. Two laser spots, laser energy and bed feed are considered as experimental parameters. Thermal camera was utilized to record the temperature change of the deposition process. The geometric dimensions and the hardness value are measured after deposition.
According to the results, the laser in the deposition direction mainly produced a molten pool on the substrate, while another laser melt the wire and deposit it. Using higher laser energy will produce a higher deposition width, and lowering the table feed will increase the deposition height. The highest hardness value will be found in the melt pool of the first layer because of the rapid heat dissipation capacity. The hardness will be stably maintained at 185 HV until the third layer. Using the 375 Watt energy parameter, the layers will be fused stably, resulting in a thin-walled structure.

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