Abstract
To address the issues of low curing depth and high viscosity in VPP slurries caused by the high refractive index and hydrophilic surface of silicon nitride (Si3N4), this study proposes a novel surface modification method. The process starts with the pre-coating of Si3N4 powder using the silane coupling agent KH570. This is followed by an oxidation step that forms a uniform SiO2 layer on the powder surface, effectively reducing the refractive index mismatch between Si3N4 and the resin, as well as minimizing light scattering. The KH570 pre-coating also protects the Si3N4 lattice, mitigating oxidation-induced damage and preserving structural integrity. Subsequently, the Si3N4 powder undergoes further modification with the silane coupling agent KH560 to enhance the slurry’s flowability and stability. Using this three-step method of pre-coating, oxidation, and surface modification, a Si3N4 slurry with 45 vol.% solid content was successfully prepared. The slurry’s viscosity decreased by 20-30%, and under a laser power of 1200 mW, the curing depth increased by 52.9%, reaching a value of 192.7 μm with a viscosity of 7.69 Pa·s (at a shear rate of 30 s⁻1 and 47.8 rpm). This approach enables the fabrication of high-quality Si3N4 ceramic components with intricate geometries.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call