Problems of YAG nanopowders compaction for laser ceramics

Slip casting and colloidal slip casting at high pressure of yttrium aluminum garnet powders were investigated. It was found that the presence of residual pores in laser oxide ceramics was determined mainly by big size pores in the compact. The size of pore in compact is critical when it is greater than the mean size of initial particles. It was shown that formation of pores’ structure in compact was controlled by appearance of quasi-particles in heavy loaded slurry. Pores concentration is critical for ceramics optical transmittance.

Research highlights► Fabrication of pore-free Y3Al5O12 ceramics requires careful compaction process. ► Pores’ size in the compact should be smaller than particle size of initial nanopowder. ► Greater pore size is due to particles agglomeration in slurry for slip casting. ► Casting under high pressure increases possible compact thickness and uniformity. ► Pores concentration is critical for the ceramics optical transmittance.