High strength mullite-bond SiC porous ceramics fabricated by digital light processing

Autor: Jian Sun, Jingde Zhang, Xu Zhang, Zihe Li, Jianzhang Li, Sijie Wei, Weibin Zhang, Weili Wang, Guifang Han
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: Journal of Advanced Ceramics, Vol 13, Iss 1, Pp 53-62 (2024)
Druh dokumentu: article
ISSN: 2226-4108
2227-8508
DOI: 10.26599/JAC.2024.9220835
Popis: Fabricating SiC ceramics via the digital light processing (DLP) technology is of great challenge due to strong light absorption and high refractive index of deep-colored SiC powders, which highly differ from those of resin, and thus significantly affect the curing performance of the photosensitive SiC slurry. In this paper, a thin silicon oxide (SiO2) layer was in-situ formed on the surface of SiC powders by pre-oxidation treatment. This method was proven to effectively improve the curing ability of SiC slurry. The SiC photosensitive slurry was fabricated with solid content of 55 vol% and viscosity of 7.77 Pa·s (shear rate of 30 s−1). The curing thickness was 50 μm with exposure time of only 5 s. Then, a well-designed sintering additive was added to completely convert low-strength SiO2 into mullite reinforcement during sintering. Complex-shaped mullite-bond SiC ceramics were successfully fabricated. The flexural strength of SiC ceramics sintered at 1550 ℃ in air reached 97.6 MPa with porosity of 39.2 vol%, as high as those prepared by spark plasma sintering (SPS) techniques.
Databáze: Directory of Open Access Journals