تاثير ميزان گرافيت و رزين بر خواص ديرگدازهاي دولوما گرافيتي

The Effect of Graphite and Resin Contents on the Properties of Doloma-Graphite Refractories

High refractoriness, chemical resistance to slag, production possibility of clean steel, environmental compatibility and low cost are some of the advantages of Dolomite refractories in steel industry. Because of availability of dolomite in Iran, production of these refractories is profitable. One kind of the Dolomite refractories is Doloma Graphite refractories that because of good resistance to corrosion and thermal shock have wide usage in cement and steel industries. In this research, the properties of Dolomite-Graphite refractories with different additives and tempering condition were evaluated. The samples were manufactured with different grain size distribution of Dolomite and various amounts of Graphite and resin. The raw materials and their thermal behaviors were studied by XRF, XRD and STA. After preparing the samples, the physical and mechanical properties, slag corrosion and thermal shock resistances were evaluated. The properties of the samples were evaluated up to 11% total Carbon in the system. The reduction in MOR of the specimens, before and after heat treatment was determined as a measurement of thermal shock resistance. The slag corrosion test was conducted based on the crucible test, at 1600°C for 5 hrs. Then, the depth of penetration was measured. The obtained results showed that due to the gradual changes in thermal behavior of resin and its weight reduction, the low temperature properties of the system were affected. The results showed that CCS of the samples was increased at the beginning and then decreased, when Graphite was added to the system. The thermal shock and slag corrosion resistance were also improved by adding graphite to the system.