Fabrication of Nd:YAG Laser Ceramics via Fused Deposition Modeling

To address the thermal management issues during the diode laser pumping process, solid-state laser gain media have been developed into various shapes and configurations. As a typical additive manufacturing technique, fused deposition modeling (FDM) exhibits advantages such as low requirements on feedstock rheology and the capability to fabricate multi-component and large-sized ceramic samples with complex shapes. In this study, the FDM method was applied to form Nd:YAG laser ceramics. The green bodies underwent a combined debinding process involving both solvent extraction and thermal treatment. After that, the samples were densified by vacuum sintering and followed by hot isostatic pressing. The in-line transmittance at 1064 nm of the Nd:YAG laser ceramic approaches 83.9%. With an output coupling mirror transmittance of 30%, the 3×3×6 mm 3 sample achieved a maximum output of 7.7 W under the diode laser pump power of 20.0 W, corresponding to a slope efficiency of 40.7%. The FDM method has shown great potential for the fabrication of high optical quality laser ceramics with complicated configurations.