Unveiling crystallographic texture in laser floating zone melted Al₂O₃/YAG eutectic ceramic by seed-crystal inducing

This study demonstrated the unique crystallographic features in Al₂O₃/YAG eutectic by seed-crystal inducing in laser floating zone melting (LFZM) process for crystallographic orientation control. The as-fabricated eutectic ceramics induced by different single crystalline seeds were mainly composed of randomly oriented Al₂O₃ faceted particles and irregular eutectic, as a result of the initial uncoupled growth at the junction of seed and eutectic. Specifically, along the direction of directional solidification, the eutectic ceramics grew stably with a single crystallographic orientation relationship with low planar disregistry (2 %∼6 %). The stability of phase interface with minimum interfacial strain and better ionic charge balance in Al₂O₃/YAG eutectic has a greater effect on the regulation of the eutectic growth orientation than the constraint of the single crystalline seed.