Aqueous Tape Casting of Zirconium Diboride

Aqueous tape casting of ZrB 2 powder with sintering additives was investigated. The dispersion of ZrB 2 suspensions in aqueous media was studied and characterized in terms of zeta potential, sedimentation, and rheological measurements. A well-stabilized suspension with a high solid content (up to 45 vol%) was prepared in the alkaline pH region with 0.4 wt% Lopon 885 as the dispersant. Several suspensions with different compositions of binder and plasticizer were prepared for comparison. Crack-free green tapes with a maximum thickness of approximately 250 μm were obtained with a binder content of 18-23 wt%. The green tapes had high qualities, such as homogeneity, good flexibility, and a smooth surface. Results showed that the slurries at selected formulations met the needs of the tape-casting process.

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