Effects of Chrome Oxide Concentrate Powder on Properties of Magnesia Composite Materials

The magnesia composite materials were prepared using fused magnesia,used magnesia chrome bricks, magnesium aluminate spinel, alumina powder and chrome oxide powder as starting materials. In order to improve the performance of magnesia composite material,the influence of chrome oxide concentrate powder on the properties of magnesia composite material was researched. The apparent porosity,bulk density,cold crushing strength,linear expansion and thermal shock resistance of the specimens were determined. The results show that adding chrome oxide concentrate promotes the formation of the composite phases of three kinds of spinel,which is beneficial to the thermal shock resistance. The magnesia chrome spinel can not be formed at high temperatures theoretically,but can dissolve in the magnesia composite material. Comprehensively,the optimal addition of chrome oxide concentrate is 10. 0 mass% for the magnesia composite materials.