Camphene-based freeze-cast ZrO2 foam with high compressive strength

Highly porous zirconia ceramic bodies with interconnected pores were fabricated by freeze-casting technique using camphene-based slurries. The pore volume fraction and pore size are controllable by adjusting the initial solid content in the mixed slurries. The pores are replicas of connected dendrites of frozen camphene, which sublimed during room temperature drying. As the solid content was increased from 10 to 20 vol.%, the compressive strength was significantly increased from 19 ± 2 to 58 ± 3 MPa, and the examined porosity was decreased from 81.5 to 66.5%. This technique is considered potentially useful in producing novel porous ceramics, and introduces a new application field of freeze-casting.