Using fused magnesia and fused magnesia chrome sand as raw materials, through fine ingredients, high-pressure molding, and ultra-high temperature firing, the product has a high direct bonding rate, good particle bonding, good high-temperature volume stability, and excellent high-temperature strength. It is widely used RH, AOD, VOD and other external refining equipment and non-ferrous smelting furnaces, converting furnaces and refining furnaces.