Support-Free Ceramic Stereolithography of Complex Overhanging Structures Based on an Elasto-viscoplastic Suspension Feedstock
Support-Free Ceramic Stereolithography of Complex Overhanging Structures Based on an Elasto-viscoplastic Suspension Feedstock
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DOI：
10.1021/acsami.9b04205
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发表时间：
2019-05-22
影响因子：
9.5
通讯作者：
Song, Xuan
中科院分区：
文献类型：
--
作者：
He, Li;Fei, Fan;Song, Xuan
陶瓷立体平版印刷(CSL)是一种通过陶瓷悬浮液的层层光聚合来制造陶瓷三维(3D)物体的添加剂制造方法。CSL的一个关键挑战是需要支撑结构来建造悬挑结构，以防止因重力或工艺诱导的剪切而导致的部分损坏或变形。去除支撑结构会导致表面质量差、开裂风险高等问题。为了克服这一挑战，本文提出了一种以弹粘塑性陶瓷悬浮液为原料的CSL基陶瓷制备方法。悬架固有的强大的颗粒间阻力可以支撑悬臂，而不需要建造额外的支撑结构；设计了温控层涂层模块，以在先前沉积的材料的自由表面上方动态形成局部悬索桥，从而允许施加具有可控剪力的新鲜薄层。本文介绍了预制悬臂的材料设计和特性，并讨论了关键工艺参数及其对悬臂几何保持性能的影响。这一新工艺为制造具有复杂悬臂的陶瓷3D对象提供了可能性，例如血管网络、仿生热交换器和微反应器。
Ceramic stereolithography (CSL) is an additive manufacturing method for creating ceramic threedimensional (3D) objects via the layer-by-layer photo-polymerization of a ceramic suspension. A key challenge in CSL is that support structures are required for building overhanging structures to prevent part damage or deformation caused by gravity or process-induced shears. Removing the support structures can result in issues such as poor surface quality, high risk of cracking, etc. To overcome this challenge, this article presents a new CSL-based ceramic fabrication method that uses an elasto-viscoplastic ceramic suspension as the feedstock material. The suspension's inherently strong interparticle resistive force can support overhangs without the need for building additional support structures; a temperature-controlled layer-coating module is designed to dynamically form a localized suspension bridge above the free surface of previously deposited materials, which allows for the application of fresh thin layers with a controlled shear force. The article presents material design and characterizations and discusses key process parameters and their effects on the geometry retention of fabricated overhangs. This new process provides the potential for fabricating ceramic 3D objects with complex overhangs, such as vascular networks, biomimetic heat exchangers, and microreactors.