Laser Processing of Multi-Phase Ceramics

This research explores laser-based processing for multi-phase ceramics, offering a faster, more energy-efficient alternative to conventional ceramic fabrication. Four material systems are explored: silica-titania, alumina-iron, polymer-derived ceramic SiC-gadolinium zirconate, and polymer-derived ceramic SiC-yttrium silicate. The silica-titania study presents a novel direct CO2 laser writing approach to fabricating pure silica and silica-titania glasses with exceptional dimensional control and optical transparency, enabling fine spatial resolution, instantaneous consolidation, and eliminating post-heat treatment. Notably, the TiO2 solubility in the silica network achieved is higher than previously reported, with structures remaining crack-free and transparent up to a specific TiO2 percentage. The alumina-iron study uses the CO2 laser sintering method to process alumina-iron compositions with different volume ratios under an inert environment. The method produces well-mixed, uniform, and dense microstructures with clean bonding and minimal porosity, leveraging hercynite formation to enhance wetting at the ceramic/metal interface. The PDC SiC- GZ and PDC SiC- YS studies explore the use of ultra-fast CO₂ laser sintering and PS laser micro-machining to fabricate high-throughput composite sample arrays for protecting SiC-based CMCs in high-temperature turbine environments. By varying compositions, a diverse range of crack-free microstructures and relative densities were rapidly generated, supporting the advancement of polymer-derived functional graded coatings. Overall, this research leverages ultra-fast laser-selective convergent manufacturing (ULCM) in creating high-resolution, advanced ceramic structures with minimal post-processing. The research findings promise impactful applications in photonics, optoelectronics, and aerospace, supporting the development of robust, high-performance ceramic components.