Example 1
5 g of pure SiC whiskers with a diameter of 0.1 to 2.5 μm and a length of 2 to 50 μm were added to a 95 wt. % aqueous solution of AMP-95 and dispersed by using an ultrasonic washing machine, followed by drying.
5 g of the above obtained SiC whiskers, 200 g of high-calcium mineral powder, 150 g of Class F fly ash, and 150 g of metakaolin were mixed and dispersed by a ball mill using zirconium oxide beads having a diameter of 5 mm at a rotation speed of 150 rpm for 25 min, to give a milled material.
To a concrete mixer, the milled material, 187.5 g of a sodium water glass solution (2 modulus; 60 wt. % water content), and 87.5 g of deionized water were added and stirred at a high speed of 120 rpm for 3 min to form a slurry.
The slurry was poured into a mold and then placed into a concrete curing box for curing at 95±5% relative humidity and 23±0.5° C. for 24 h and then for 7 days in the curing box at the same conditions after removal from the mold. Finally, a SiC whiskers reinforced geopolymer material (i.e., an uncalcined geopolymer-based refractory material) was obtained.
