Wang Evelyn, Gupta Shruti, Rafalko Charles J, Lear Benjamin J, Hickner Michael A
Department of Chemical Engineering, Michigan State University, East Lansing, Michigan 48824, United States.
Department of Material Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States.
ACS Appl Polym Mater. 2025 Jul 14;7(14):8928-8936. doi: 10.1021/acsapm.5c00241. eCollection 2025 Jul 25.
We have developed near-infrared (NIR) thermal stereolithography (SLA) to print 2.5D-structured polymer-derived ceramic (PDC) composites with high SiC particle loadings in a PDC matrix. When combined with polymer infiltration and pyrolysis (PIP), this approach overcomes the challenges associated with traditional ultraviolet-based printing techniques when printing composite resins, namely, low light penetration, limited particle loadings, high shrinkage, and weak mechanical properties. Using an NIR laser to deliver spatially controlled thermal energy to the surface of a reactive resin pool induces localized thermally initiated free-radical polymerization in a top-down SLA configuration. After printing the green body, postprocessing methods, including debinding and PIP, are employed to densify and strengthen the printed samples. A Si-O-C support network was formed in the debinded samples using a small amount of preceramic polymer in the printing resin to maintain the structural integrity of this porous preform. After 5 cycles of PIP, the PDC composites demonstrated a flexural strength of 74.3 ± 13.7 MPa with a density of 2.31 g/cm. Different 2.5D lattice designs were fabricated by using this printing and materials processing method, and a compressive strength of 32.8 ± 11.2 MPa was obtained for lightweight honeycomb structures with an effective density of 1.07 g/cm.
我们开发了近红外（NIR）热立体光刻（SLA）技术，用于在聚二甲基硅氧烷（PDC）基体中打印具有高碳化硅（SiC）颗粒负载量的2.5D结构聚合物衍生陶瓷（PDC）复合材料。当与聚合物浸渍和热解（PIP）相结合时，这种方法克服了在打印复合树脂时与传统紫外光基打印技术相关的挑战，即低光穿透率、有限的颗粒负载量、高收缩率和较弱的机械性能。使用近红外激光将空间控制的热能传递到反应性树脂池表面，在自上而下的SLA配置中引发局部热引发自由基聚合。打印生坯后，采用包括脱脂和PIP在内的后处理方法来致密化和强化打印样品。在脱脂样品中，使用打印树脂中的少量陶瓷前体聚合物形成了Si-O-C支撑网络，以保持这种多孔预成型体的结构完整性。经过5个循环的PIP后，PDC复合材料的弯曲强度为74.3±13.7MPa，密度为2.31g/cm。通过这种打印和材料加工方法制造了不同的2.5D晶格设计，对于有效密度为1.07g/cm的轻质蜂窝结构，获得了32.8±11.2MPa的抗压强度。
