陶瓷面曝光快速成型工艺研究

Ceramics Fabrication Using Rapid Prototyping of Mask Projection Stereolithography

利用投影机中微小反射镜阵列(Digital micromirror device,DMD)形成投影图案,以发光二极管紫外光(UV-LED)作为光源,建立了陶瓷面曝光快速成型试验系统。利用该系统研究了自开发的可光固化磷酸钙陶瓷浆料的光固化性能,确定了其临界曝光强度为14.24 mJ/cm^2,透射深度为149μm;优化了面曝光陶瓷成型的工艺参数,即分层厚度100μm,曝光强度54 mJ/cm^2,曝光时间3 s,并实现了带有复杂网状结构的陶瓷多孔支架的制造。该工艺所成型的陶瓷零件经烧结后,其致密表面和内部未见有裂纹和较大孔洞,压缩强度高达63MPa,可满足骨组织工程支架的机械性能要求。所述的面曝光快速成型工艺可直接成型多孔以及复杂结构的陶瓷零件,有望为陶瓷骨组织支架的制造提供新的发展方向。

The aim of this study is to present a ceramics forming technique based on the mask projection stereolithography with a UV-LED light, which can impel homemade photo-curable β-TCP ceramic slurry to cure. During the manufacturing, the various masks can be dynamically created by a digital micromirror device （DMD） through switching on and off the small mirrors. By experiments, the photo curable properties of homemade ceramic slurry are determined for the critical exposure intensity（Ec） of 14.24 mJ/cm2 and the penetration depth （Dp） of 149 pro. Process optimizing parameters are determined for 1001arn layer thickness, 54 mJ/cm2 exposure intensity and 3 s exposure time. Porous ceramic scaffolds were fabricated with complex network structure. No cracks and obvious holes are found in the surface and interior of sintered ceramic parts, whose compressive strength is up to 63 MPa, which can satisfy the mechanical requirement of the bone tissue engineering application. Therefore, the mask projection for ceramic stereolithography presented in this work is feasible to directly print porous and complex structure of ceramic green parts, which is expected to simply make ceramic bone scaffolds with complex structure.