To Study the Effect of Addition of Nano Ni Particles as Catalyst on Microstructure and Properties of MgO C Refractory

Magnesia-carbon (MgO-C) refractory bricks have been used in the slag line of ladles due to its superior slag penetration resistance and excellent thermal shock resistance at high temperatures. However, the life of this bricks has become limited on prolonged use due to its poor oxidation resistance as well as low strength at high temperatures. Thus, the physical and chemical properties of MgO-C refractories could be improved by the use of nanotechnology and addition of suitable additives nano range. Metallic nano-Ni particles has been recognized as one of the most effective nanomaterial to be used in MgO-C refractory as it has large surface area and density which lead to the development of various in-situ ceramic phases in the refractories which enhances its properties. Hence, the present work deals with the improvement of the physical and chemical properties of MgOC refractories with the addition of nano-Ni particle as catalyst. In this work, a set of experiments was carried out in order to standardize amount of nano-Ni addition in MgO-C refractory system. Here nano sized metallic Nickel particles are added in different amount (2,4,6 and 8 wt.%) in MgO-C refractory with fixed content of graphite (12 wt.%) and antioxidants B4C and metallic aluminum powder each (1wt.%). So that only the effect of nano-Ni variation in the MgO-C refractories can be evaluated. Total five compositions has been made by varying the composition of nano-Ni from (0-8 wt.%) and then compare the properties of nano-Ni added MgO-C brick with the conventional MgO- C brick, which contain 12wt.% graphite only, there is no nickel added in it. Out of the different samples containing nano-Ni in MgO-C brick, MC6 sample (containing 6 wt.% nano-Ni) exhibits better compaction, so has high bulk density (BD), cold crushing strength (CCS) and hot modulus of rupture (HMOR).