本研究主要探討選擇性雷射燒結(SLS)，於不同的預置粉末厚度下，微觀組織的差異及孔隙率之探討。藉由初始一預置粉末厚度，並將移動之雷射光熱源施加於粉末表面上進行掃描加工。數值分析部分是利用有限元素分析軟體—ANSYS以熱機非耦合之方式進行模擬，模擬掃描路徑移動之軌跡，並探討於轉角點處時，不同的雷射功率、不同的粉末預置厚度及不同的移動速度下於轉角點及掃描線段上之溫度變化。
實驗方面以連續式波長1064 nm 之Nd-YAG雷射加熱以固定比例4:1(不銹鋼:紅銅)配置之金屬粉末，利用掃描振鏡配合控制軟體控制移動的軌跡及掃描間距。以雷射功率、掃瞄速度及預置粉末厚度為實驗參數，探討雷射燒結試件之表面形貌及孔隙性之影響。模擬與實驗結果顯示，隨著預置粉末厚度增厚、雷射功率增加及較低的掃瞄速度情況下，其雷射燒結試件之成形性越佳，但是如果掃描速度為0.5mm/s時，雷射燒結試件會有破裂及翹曲之狀況產生。

This study focused on selective laser sintering (SLS) at different preset powder thickness, temperature, microstructure and discuss difference of porosity. Scanning process is completed with a preset initial powder thickness and movement of laser light source applied to the surface of the powder. Numerical analysis used finite element analysis software –ANSYS to simulate the moving heat source with uncoupled thermo-mechanical approach, and discussed different laser power and preset power thickness at the sintering temperature under different moving speed at a corner point.
The experiments were performed by heating with Nd-YAG laser at a wavelength of 1064 nm at a fixed powder ratio of 4: 1 (stainless steel: copper), and using scanning galvanometer, incorporated with control software to control moving track and scanning pitch. Laser power, scanning speed and preset powder thickness were selected as experimental parameters, where the morphology of laser sintering specimen with porosity was inspected. Among the results of simulation and experiments, it suggested that the formability of the laser sintering specimen came up better under increasing preset thickness of powder and laser power, as well as lower scanning speed; however, if the scanning speed is up to 0.5mm/s, the laser sintering specimens would ruptured with warpage.

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