Abstract Surface quality is essential for additive manufactured components due to the growing demand in various industries. This paper presents an experimental and analytical study on post-processing of selective laser sintered Polyamide 12 (PA12), aiming at improving surface quality and clarifying interrelations between surface quality and process parameters. The effects of post-processes on surface and subsurface characteristics regarding material removal, surface morphology and roughness, hardness, tribology performance were quantitatively evaluated. The results show that after post-processing, the surface roughness of the PA12 components were reduced obviously from over 15 μm Ra to 2.85 μm Ra and 0.89 μm Ra by precision grinding and magnetic field-assisted finishing (MFAF), respectively. The un-melted powder surface layer was effectively removed although the surface hardness was slightly reduced. The MFAF processed surface showed a better tribology performance represented by lower coefficient of fiction and higher wear resistance. Moreover, the results of laser Raman analysis and X-ray photoelectron spectroscopy (XPS) indicated that there were no obvious chemical changes induced on the sub-surface level within 10 μm by the post-processes.

中文翻译：

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通过精密研磨和磁场辅助精加工提高选择性激光烧结聚酰胺12的表面质量

摘要 由于各行各业的需求不断增长，表面质量对于增材制造组件至关重要。本文介绍了选择性激光烧结聚酰胺 12 (PA12) 后处理的实验和分析研究，旨在提高表面质量并阐明表面质量与工艺参数之间的相互关系。定量评估了后处理对材料去除、表面形态和粗糙度、硬度、摩擦学性能等表面和亚表面特征的影响。结果表明，经过后处理后，PA12部件的表面粗糙度通过精密磨削和磁场辅助精加工（MFAF）分别从15 μm Ra以上明显降低到2.85 μm Ra和0.89 μm Ra。尽管表面硬度略有降低，但未熔化的粉末表面层被有效去除。MFAF处理后的表面表现出更好的摩擦学性能，表现为摩擦系数更低，耐磨性更高。此外，激光拉曼分析和 X 射线光电子能谱 (XPS) 的结果表明，后处理在 10 μm 范围内的亚表面水平上没有引起明显的化学变化。