Comparison of laser‐based and solid‐state syntheses of ytterbium aluminum garnet Yb ₃ Al ₅ O ₁₂

Abstract The utility of laser‐based heating for the rapid synthesis of small quantities of ytterbium aluminum garnet (Yb₃Al₅O₁₂, YbAG), a high‐temperature ceramic material, was demonstrated. YbAG was synthesized in air using a 400 W carbon dioxide (CO₂) laser in a copper hearth, starting from ytterbia (Yb 2 O 3 ) and alumina (Al 2 O 3 ) powders. The process produced spheroidal YbAG beads in a single step through the direct reaction of the mixed oxides. For comparison, YbAG was also synthesized as a pellet via solid‐state reaction in an electric box furnace. The resulting phases and microstructures of both a laser‐synthesized bead and the furnace‐synthesized pellet were characterized using X‐ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The laser‐synthesized beads were predominantly single‐phase YbAG, with minor eutectic formation of Al₂O₃ and YbAG in one bead at grain boundaries and pores. Laser‐based synthesis proved to be a fast and efficient method for producing small quantities of high‐temperature ceramic powders. Although not a novel technique, laser heating is rarely applied in high‐temperature materials synthesis. The rapid reaction observed here suggests the potential for forming YbAG coatings through a combined reaction and deposition process during thermal spray methods.