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Magnesia-Doloma refractories has advantages such as stability in alkaline environments, clean steel production, resistance to acid slag, good cement kiln coating flexibility, low production cost. It also has some weaknesses such as low resistance to thermal shock and quick hydration. In the present study using Birjand Mines Magnesite powders and Dolomites from Zefreh, Esfahan, Magnesia-Doloma clinkers were pressed under the pressure 90 MP and prepared at 1650⁰C in furnace under air atmosphere. The effect of adding 0, 2, 4, 6, and 8% of the Microparticles and Nanoparticles of α-Alumina on microstructure, physical properties, hydration resistance and Thermal shock resistance was studied. Phase... 

Magnesia–Doloma refractories are considered as a mixed product of alkali products i.e. sintered (fused) magnesia and doloma in which 50-80 wt% magnesia is contained. These refractories enjoy some advantages such as high slag resistance corrosion, high-temperature performance, potential for production of pure molten iron and low cost due to abundance of magnesia and doloma resources in access. However, there exist some problems with these refractories that render them unsuitable for some applications. Among these cases, poor resistance of hydration can be cited that may constrain the amount of this refractory in various industrial applications. In the present work, the addition effect of... 

Magnesia-doloma refractories are alkaline products made by combining sintered or fused dolomite and magnesite. These refractories contain 50-80 wt% magnesium and a higher percentage of magnesium oxide, provides desirable properties such as improved refractoriness and resistance to air moisture absorption. Magnesia-doloma refractories have significant weaknesses, including rapid hydration due to the presence of CaO and MgO phases. These refractories are also primarily used with carbon additives in the industry, where increasing the carbon weight percentage in these refractories weakens their strength and some of mechanical properties. In the present study, the effect of adding carbon...