積層製造可使產品在設計上具有高度靈活性，高強度的材料已無法滿足設計者的需求，因此具有彈性的高分子材料逐漸成為市場上的新型功能材料，高分子粉末積層製造主要是以選擇性雷射燒結為主軸，在列印過程中藉由雷射之能量使粉末燒結成型，若在燒結過程中能量密度無法使粉末燒結成型，可在粉末中添加碳黑使反射率降低來增加對能量的吸收。
在使用Sinterit公司生產的TPU粉末時，發現其粉末經震動後會發生粉碳分離之現象，利用分光光譜儀進行檢測，其反射率測試值呈現高低起伏，造成燒結過程中能量吸收不平均而影響到成品品質，因此本研究使用碳黑包覆製程製備複合粉末以改善粉碳分離之情形並提升列印性質。以波長808 nm之半導體單雷射進行列印，並在相同波長比較不同碳黑比例之複合粉末的光反射率、雷射能量密度與預熱溫度，在各不同參數下對於列印成品之影響。
使用碳黑包覆製程製備之複合粉末不會產生粉碳分離的狀況，並且能使碳黑均勻的附著於粉末表面，可使反射率下降。針對預熱溫度、雷射能量密度、鋪粉層厚與碳黑添加量及反射率進行實驗，發現列印區預熱溫度75℃、能量密度0.028 J/mm2、層厚0.125μm與碳黑添加量0.4wt%及反射率13.81%下得到最高平均成型密度1.09 g/cm3、邵氏硬度78A、拉伸強度7.9MPa，伸長量364.9%，並與未進行碳黑包覆之複合粉末進行比較，其反射率下降1.78%，機械性質增加33.9%，且燒結成品之孔隙明顯變小。

Additive manufacturing can make products highly flexible in design. High-strength materials can no longer meet the needs of designers. Therefore, elastic polymer materials have gradually become new functional materials in the market, the additive manufacturing of polymer powder is mainly based on selective laser sintering. During the printing process, the powder is sintered by the energy of the laser. If the energy density cannot make the powder sintered during the sintering process, can be added the carbon black to the powder to reduce reflectivity to increase energy absorption.
When using the TPU powder produced by Sinterit, it was found that the powder and carbon would separate, and the spectrometer was used to detect it. The reflectance test value fluctuated, resulting in uneven energy absorption during the sintering process and affecting the quality of the finished product. Therefore, this study used the carbon black coating process to prepare the composite powder to improve the separation of powder and carbon and enhance the printing properties. A single semiconductor laser with a wavelength of 808 nm was used for printing, and the light reflectivity, laser energy density, and preheating temperature of the composite powder with different carbon black ratios were compared at the same wavelength and the effects on the printed product under different parameters.
The composite powder prepared by the carbon black coating process will not cause the separation of powder and carbon, and the carbon black can be uniformly attached on the powder surface, which can reduce the reflectivity. Experiments were carried out at the preheating temperature was 75℃, laser energy density was 0.028 J/mm2, powder layer thickness was 0.125μm, carbon black addition was 0.4wt%, and reflectivity was 13.81%. The highest average density of 1.09 g/cm3, Shore hardness of 78A, the tensile strength of 7.9MPa and elongation of 364.9% were obtained. Compared with the composite powder without carbon black coating, the reflectance decreased by 1.78%. The properties increased by 33.9%, and the porosity of the sintered product became significantly smaller.

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