Effect of Chromium on Stereolithographic Printing with Alumina-Based Slurries

Abstract

We have studied the effect of small Cr₂O₃ and Cr³⁺ additions on the optical properties of high-purity alumina-based powders and photocurable slurries for 3D printing. The polymerization depth of the slurries has been shown to strongly depend on the amount of the coloring additive in the Al₂O₃ powders. Using digital light processing (DLP) 3D printing followed by high-temperature sintering, we have obtained thin-walled planar samples of high-density periodic-structure ceramics and studied their microstructure and luminescence properties. Their photoluminescence spectrum contains a sharp strong line in the red spectral region, at 694 nm (characteristic line of ruby). The luminescence decay curves showed single-exponential behavior with a decay time of ~3.7 ms.