Creep and high temperature bending behaviors were examined on the SiC refractories bound by silicate in the presence of V2O5 fired at 1000～1400℃ with bending strength of 150MPa or higher at room temperature. Creep tests under 20 MPa load were conducted at 1300℃ in air. The SiC compacts fired at 1300℃ and 1400℃ indicated low creep strain, 0.07％ at 1300℃ of testing temperatures. The bending strength of the compacts fired at 800～1300℃ was over 100 MPa at 1300℃. High temperature properties were characterized by the identification of phases and the microstructural observation using TG-DTA, XRD and SEM･EDX.

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The effect of MgO and ZrO2 addition was investigated on the spalling resistance of CaO brick. Ｔｈｅ spalling resistance has improved greatly by optimizing the amount of MgO and ZrO2 addition because the addition of both MgO and ZrO2 generates a lot of cracks in the brick. The relational formula of porosity and strength was obtained on the spalling resistance of CaO brick by considering the existence of comparatively large initial crack （Griffith crack）. In addition, the effect of the MgO addition on the reaction on CaO-ZrO2 system was investigated. The CaO-ZrO2 system is not densified at the high temperature by the MgO addition. Moreover, the reaction product of Ca0.15Zr0.85O1.85 exists besides CaZrO3. Especially, it was cleared that the effect of Ca0.15Zr0.85O1.85 was much in the heating process and the initial stage of reaction.

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