El Magri Anouar, Bencaid Salah Eddine, Vanaei Hamid Reza, Vaudreuil Sébastien
Euromed Research Center, Euromed Polytechnic School, Euromed University of Fes, Route de Meknès (Rond point Bensouda), Fes 30 000, Morocco.
Léonard de Vinci Pôle Universitaire, Research Center, 92916 Paris La Défense, France.
Polymers (Basel). 2022 Sep 4;14(17):3674. doi: 10.3390/polym14173674.
Poly(dodecano-12-lactam) (commercially known as polyamide "PA12") is one of the most resourceful materials used in the selective laser sintering (SLS) process due to its chemical and physical properties. The present work examined the influence of two SLS parameters, namely, laser power and hatch orientation, on the tensile, structural, thermal, and morphological properties of the fabricated PA12 parts. The main objective was to evaluate the suitable laser power and hatching orientation with respect to obtaining better final properties. PA12 powders and SLS-printed parts were assessed through their particle size distributions, X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), a scanning electron microscope (SEM), and their tensile properties. The results showed that the significant impact of the laser power while hatching is almost unnoticeable when using a high laser power. A more significant condition of the mechanical properties is the uniformity of the powder bed temperature. Optimum factor levels were achieved at 95% laser power and parallel/perpendicular hatching. Parts produced with the optimized SLS parameters were then subjected to an annealing treatment to induce a relaxation of the residual stress and to enhance the crystallinity. The results showed that annealing the SLS parts at 170 °C for 6 h significantly improved the thermal, structural, and tensile properties of 3D-printed PA12 parts.
聚（十二烷-12-内酰胺）（商业上称为聚酰胺“PA12”）因其化学和物理性质，是选择性激光烧结（SLS）工艺中最具资源利用价值的材料之一。本工作研究了两个SLS参数，即激光功率和扫描方向，对制造的PA12零件的拉伸、结构、热和形态性能的影响。主要目的是评估获得更好最终性能的合适激光功率和扫描方向。通过PA12粉末和SLS打印零件的粒度分布、X射线衍射（XRD）、傅里叶变换红外光谱（FTIR）、差示扫描量热法（DSC）、扫描电子显微镜（SEM）及其拉伸性能进行评估。结果表明，在使用高激光功率时，扫描过程中激光功率的显著影响几乎不明显。机械性能的一个更重要条件是粉末床温度的均匀性。在95%激光功率和平行/垂直扫描条件下达到了最佳因子水平。然后对采用优化SLS参数生产的零件进行退火处理，以消除残余应力并提高结晶度。结果表明，在170°C下对SLS零件进行6小时的退火处理，显著改善了3D打印PA12零件的热、结构和拉伸性能。
