Barium titanate foam ceramics and preparation method thereof

A preparation method of barium titanate foam ceramics, comprising the following steps:

• (1) by weight, 100 parts of nano barium titanate and 30 to 120 parts of an aqueous solution of organic binder with a concentration of 1 to 15 wt % are sufficiently ground to obtain a slurry A;
• 10 to 80 parts of an aqueous solution of organic rheological agent with a concentration of 0.5 to 3 wt % are added into the slurry A, and the mixture is sufficiently ground to obtain a slurry B;
• 20 to 80 parts of an aqueous solution of organic dispersant with a concentration of 0.5 to 3 wt % are added into the slurry B, and the mixture is sufficiently ground to obtain a slurry C;
• (2) a polymer sponge having a specification of 15 to 35 PPI is soaked in an aqueous solution of sodium hydroxide with a concentration of 5 to 20 wt %, and then heated up to 50 to 75° C. and kept at that temperature for 2 to 6 h, the polymer sponge is taken out and washed with deionized water, dried to obtain a polymer sponge D;
• at room temperature, the polymer sponge D is soaked in an aqueous surfactant solution with a concentration of 0.5 to 3 wt % for 2 to 6 h, then taken out and removing the excess surfactant, after dried at 40 to 80° C., a pretreated polymer sponge E is obtained;
• (3) the pretreated polymer sponge E is soaked in the slurry C prepared in step (1), and maintained for 1 to 10 min at room temperature, after hanging pulp, the excess slurry in the sponge is removed by extrusion, and the sponge is dried at 40 to 80° C.;
• repeating the processes of hanging pulp and drying for 1 to 7 times to obtain a green body of foam ceramics based on barium titanate;
• (4) the green body of barium titanate foam ceramics prepared in step (3) is heated from room temperature to 100-300° C. at a rate of 0.5-5° C./min, and then raised to 500-700° C. at a rate of 0.5-5° C./min and maintained at 500-700° C. for 0.5-2 h, after that, continuously heated to 1000-1500° C. at a rate of 2-10° C./min and kept at 1000-1500° C. for 1-5 h, cool with the furnace to room temperature to obtain barium titanate foam ceramics.