MgO%≥60 Cr2O3%≥12 SiO2%≤3.0 0.2Mpa荷重软化开始温度℃ Initial Soften Temp, Under Load 0.2Mpa ≥1580 显气孔率(%) Apparent Porosity %≤19 常温耐压强度Mpa Cold Crushing Strength Mpa≥35