In order to improve the strength of additive manufacturing silicon carbide, Ge Zhang's research team in the Key Laboratory of advanced manufacturing technology of optical systems of the Chinese Academy of Sciences previously applied the core product of HOOKE INSTRUMENTS - P300 confocal Raman spectrometer to study the feasibility of precursor impregnation cracking on green billets (ceram. Int. - based on Raman spectroscopy technology to explore the performance law of SiC ceramics prepared by reactive melt infiltration method), Then he further studied the influence of carbon content in the green body on material performance, and published the article "Microstructure Evolution and Performance Improvement of Silicon Carbide Ceramics via Impregnation Method" in Materials.

Abstract

The high topological silicon carbide (SiC) ceramics can be prepared by stereolithography (SLA) combined with liquid silicon infiltration (LSI) techniques. This paper aims to enhance the performance of SiC ceramics prepared by SLA and LSI techniques via the cyclic impregnation/carbonization of the precursor of carbon source solution before LSI. The effects of impregnation/carbonization cycles on the microstructure and properties of C/SiC preform and sintered body were analyzed in detail. The results show that, with the increase of impregnation/carbonization cycles, the porosity in the C/SiC preform decreases obviously and the content of secondary SiC in the sintered body increases effectively. Especially, when the impregnation/carbonization cycle was performed twice, the sintered body had the optimal mechanical properties. The value of flexural strength, bulk density and elastic modulus were 258.63 ± 8.33 MPa, 2.95 ± 0.02 g/cm3 and 425.16 ± 14.15 GPa, respectively. In addition, the thermal dimensional stability of sintered body was also improved by this method. This method proves that SiC ceramics prepared by SLA combined with LSI have the potential of applications in space optical mirrors.

The paper links:

https://doi.org/10.3390/ma15051717