Yongkang Yang,Xiqing Xu,Boran Wang,Shiyuan Li,Ziqi Jia,Xusen Guo,Shuhuai Wang,Shuxin Niu,Xin Li
Vat photopolymerization (VPP) 3D printing technology is suited for intricate ceramic core forming due to its design freedom. However, solving the lateral over-cure width while formation is crucial. Graphene was used in VPP-3D printing of silica-based ceramic cores to examine its effects on forming and sintering, and a desirable curing coefficient was presented to evaluate the forming accuracy of single layer. A straightforward model using a modified Beer–Lambert law based on exposure time rather than exposure power predicts the effect of graphene on the VPP process at consistent curing depth and exposure time and clarifies how the curing process affects flexural strength and surface quality. The optimal graphene content was determined by double bond conversion rate, structural anisotropy, and mechanical properties. Increasing graphene concentration reduces curing sensitivity and exposure time threshold, allowing more liquid phase to cure and improving double bond conversion and interlayer bonding. However, excess graphene increases the conversion rate and stress concentration of green body. According to microstructural studies, extra graphene enhanced the likelihood of crack reformation after sintering. The ceramic cores had optimal forming and sintering capabilities with 0.6 wt.‰ graphene content. The approach offers significant insights for enhancing VPP ceramic 3D printing.
Vat photopolymerization (VPP) 3D printing technology allows the fabrication of complex ceramic structure components through the layer-by-layer stacking strategy. The curing depth is a crucial parameter for the stacking process, as it directly impacts the printing quality. Furthermore, this parameter exerts a profound effect on the final quality of the printed part. However, there is currently a lack of comprehensive research on how the curing depth affects VPP ceramic 3D printing . This study aims to thoroughly evaluate the impact of curing depth parameters on critical aspects of the 3D printing process, including the forming accuracy, surface quality, monomer conversion , resin pyrolysis , interlayer defects, and mechanical properties. The results of our investigation clearly demonstrate the significant influence of curing depth on the precision and performance of VPP 3D printed ceramic parts. Ceramic samples produced with higher curing depth exhibited superior surface quality (Ra<1.6 μm) but lower forming accuracy. Increasing the curing depth improved interlayer adhesion but excessive depth led to a decreased monomer conversion content from 5.2 % to 2.0 % and an internal stress in the green body. Moreover, increasing the curing depth intensified the pyrolysis process and increased the propensity for cracks forming, as confirmed by simultaneous thermal analysis and microstructure observations . The flexural strength of the sintered samples reached its maximum value of 630 MPa at three times the printing layer thickness. This study provides valuable insights for selecting appropriate curing depth parameters in VPP ceramic 3D printing.
危险品化学品经营许可证（带存储）