Danna Tang,Kai Yang,Tianyu Gao,Tingting Liu,Haibin Tang
Mechanical-electromagnetic integrated design has great potential in the development of electromagnetic shielding equipment for military use. In this study, Al 2 O 3 /SiO 2 ceramics with triply periodic minimal surfaces (TPMSs) were fabricated using digital light processing (DLP) technology. The preparation of SiO 2 and Al 2 O 3 powders is vital for DLP because minimal aggregates or sedimentation in the ceramic paste is required. Debinding and sintering programs were developed to prevent defects in the designed microstructure. The interfacial characterization demonstrated that the surfaces of the sintered ceramics were compact and smooth. The compression strength of the TPMS ceramic with a volume fraction of 50% was 24 MPa, which is relatively good among additively manufactured cellular ceramics. The TPMS structures also exhibited significant electromagnetic interference (EMI) shielding effectiveness in the X-band (2 to 18 GHz), and the shielding performance was adequate to meet the demands of electromagnetic shielding materials . Additive manufacturing of Al 2 O 3 /SiO 2 ceramic with TPMS architectures was successfully achieved by considering the mechanical-electromagnetic integration.
Zijun Peng,Lei Yuan,Xudong Luo,Jingkun Yu,Chen Tian,Zhenli Liu
MgO–Al 2 O 3 –SiO 2 composite ceramics were prepared by spark plasma sintering (SPS). In addition, phase composition, microstructure, mechanical properties , and thermal shock properties have been systematically characterized. Introduction of Al 2 O 3 and SiO 2 significantly increased mechanical properties and thermal shock resistance of these composite ceramics. MgO–Al 2 O 3 –SiO 2 composite ceramics prepared by spark plasma sintering (SPS) exhibited fine grain size. Reduced grain size may result in extraordinary properties. Experimental results showed that MgO–Al 2 O 3 –SiO 2 composite ceramics had the highest flexural strength and hardness among all studied ceramics of 269.6 ± 9.22 MPa and 12.51 ± 0.29 GPa, respectively. Moreover, MgO–Al 2 O 3 –SiO 2 composites can reach 16 thermal cycle times. This shows that it is feasible to prepare high-performance MgO composite ceramics by SPS. Furthermore, introduction of Al 2 O 3 and SiO 2 is effective method to improve mechanical properties and thermal shock resistance of MgO composite ceramics.
危险品化学品经营许可证（带存储）