Patent ID: 6843304

Claim:
A ceramic plate material for the side dams of a twin-drum strip caster, the ceramic plate material consisting of, in terms of mass %, BN of not less than 5% to not more than 20%, AlN of more than 15% to not more than 40% and Si 3 N 4 of not less than 40% to not more than 80%, Al of 9 mass % or more in terms of Al equivalent, and having the properties of: bending strength at room temperature of not less than 120 MPa, bending strength at 1,000° C. of not less than 65 MPa, hardness (Hv) of 50 to 350, fracture toughness K IC at 1,000° C. of not less than 1 MPa·m 1/2 , thermal conductivity at a temperature from room temperature to 1,000° C. of not more than 8 W/(m·K), thermal shock resistance index R′ of not less than 800 W/m, and wettability with molten steel (contact angle θ) of not less than 120°.