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In this work, the static water and oxygen corrosion behavior of SiCf/SiC–SiYBC composites was systematically studied at 1 300°C to 1 500°C. With the increase in corrosion temperature from 1 300°C to 1 500°C, both the residual strength and strength retention rate of SiCf/SiC–SiYBC composites initially increased and then decreased. The highest strength retention rate achieved was 132%, which was 35% higher than that of SiCf/SiC composites. During water and oxygen corrosion of composites, self‐healing boron silicate glass and the Y2Si2O7 phase with excellent resistance to water and oxygen were generated in situ. The oxidation products are fluid at high temperatures and can fill internal pores and microcracks, thus improving the residual strength of the SiCf/SiC–SiYBC composite. The water corrosion resistance of SiCf/SiC–SiYBC materials has been confirmed to be superior to that of SiCf/SiC composites. [ABSTRACT FROM AUTHOR]

A series of photosensitive zirconia ceramic slurry with adjustable viscosity and cured depth have been presented for the construction of high‐quality zirconia ceramic fabricated by digital light processing 3D printing. The rheological and curing behavior of the slurry can be flexibly optimized by tuning the reactive diluent concentration and category, since the change of dominant position of diluent on viscosity and the different curing mode. Monofunctional reactive diluent (HEA, hydroxyethyl acrylate) exhibits an enhanced dilution effect compared with that of bifunctional reactive diluent (HDDA, 1,6‐hexamethylene diacrylate) due to the lower molecular mass of monofunctional diluent. As a result, the viscosity reaches lower than 2000 mPa·s when the concentration of both HEA and HDDA exceeds 50 wt.%. At the same time, the non‐Newtonian properties of the slurry are also changed, which facilitates the printing process. However, excessive addition of diluent may generate more defects in ceramic green body. Consequently, the cured depth of zirconia slurry can reach 55 and 50 µm, respectively, at the curing time of 3 s while introducing the HEA or HDDA with the concentration below 70 wt.%, and the modified feedstock is promising for high‐quality and low‐defect zirconia ceramic components printing for biomedical applications. [ABSTRACT FROM AUTHOR]

In this work, alumina was selected as the second phase reinforced fused quartz ceramics and SiO2–Al2O3 composite ceramics were fabricated via digital light processing (DLP) 3D‐printing. The effect of the sintering procedure on the mechanical and dielectric properties of SiO2–Al2O3 composite ceramics were investigated in detail. The results show that the amount of cristobalite precipitation is the key factor affecting the properties of composite ceramics. The amount of cristobalite precipitation in composite ceramics could be controlled effectively by adjusting the heating rate, holding time, and sintering temperature. The sintering procedure is set as the heating rate of 4°C/min, sintering temperature of 1200°C, and holding time for 2 h, the flexural strength of SiO2–Al2O3 composite ceramic is 47.13 MPa, dielectric constant ranges from 2.90 to 2.97, and the tangent of loss angle is less than 0.041. SiO2–Al2O3 composite ceramics with high flexural strength and low dielectric constant were obtained by sintering procedure screening and optimization. [ABSTRACT FROM AUTHOR]