The Study Of Chrome-free Unburned Brick Used RH Furnace Lower Tank

In recent years, non-chrome refractories research is the development trend of the refractory industry. In order to achieve of RH furnace without chromium, 97 fused magnesia and magnesium aluminate spinel was prepared periclase- spinel unburned brick. First, determine the particle size and amount of spinel; the second step, determine the type and amount of binder; the third step, investigate the effect of additives on the properties of periclase- spinel unburned brick. The results show that:(1)When adding 0-1mm sizes pinel, the periclase-spinel brick has better thermal shock resistance.When adding 15% spinel, the periclase-spinel brick has higher bulk density, homoeothermy flexural strength,homoeothermy compressive strength and lower porosity.(2)The method of slag erosion brick is chemical reaction and infiltration. Slag erosion makes the structure of the refractory osteoporosis and low melting point substance C4 AF makes spinel dissolved,destroying the strength and thermal shock resistance of the refractory materials.(3)The periclase- spinel unburned brick that using phenolic resin as binder has a higher bulk density, homoeothermy flexural strength,homoeothermy compressive strength and lower porosity than which using hexametaphosphate as binder. The periclase- spinel unburned brick which using hexametaphosphate as binder, has better thermal shock resistance.(4)The sample which using phenolic resin and sodium hexametaphosphate composite binder, with the phenolic resin content increase, the bulk density increase, homoeothermy flexural strength and homoeothermy compressive strength become higher. When the content that phenolic resin:hexametaphosphate is three, the thermal shock resistance of the sample is best. Colligating various properties of sample, when adding 4% composite binder(phenolic resin:hexametaphosphate=2:2), the periclase-spinel unburned brick has a better comprehensive performance.The periclase- spinel unburned brick when adding iron oxide, the erosion resistance is poor; adding titanium oxide and zirconium oxide can prevent the penetration of slag; adding copper oxide can reduce the erosion resistance. When the amount of titanium oxide is 3%, the slag resistance of the periclase- spinel brick is the best.