CaO-ZrO2 composition, method for producing CaO-ZrO2 composition, CaO-ZrO2-containing refractory material, and casting nozzle

The ZrO2-CaO-C refractory material provided by the invention has remarkable hydration resistance and self-fluxing resistance, so that the ZrO2-CaO-C refractory material has corrosion resistance and can maintain high adhesion resistance for a long time. This refractory material contains a CaO-ZrO2 composition which contains a CaO component in an amount of 40 to 60 mass% inclusive, has a CaO/ZrO2 component mass ratio of 0.67 to 1.5 inclusive, contains a eutectic structure of CaO crystals and CaZrO3 crystals, and has a width of the CaO crystals, which can be observed in the cross-sectional structure, of 50 [mu] m or less. 本发明提供一种ZrO2-CaO-C类耐火材料，其具备显著的抗水化性，抑制自熔性，于是在具备耐腐蚀性的同时可长时间维持较高的难附着性。本发明的耐火材料含有CaO-ZrO2组合物，该CaO-ZrO2组合物将CaO成分含有40质量％以上、60质量％以下，CaO/ZrO2成分的质量比为0.67以上、1.5以下，含有CaO结晶与CaZrO3结晶的共晶组织，而且在截面的组织中可观察到的CaO结晶的宽度为50μm以下。