Rod-like h-BN modified low carbon Al2O3-C refractory and its high-temperature service performances

Rod-like h-BN with an average diameter of 2 mu m was synthesized at a relatively low temperature of 1200 degrees C through a catalytic pyrolysis precursor strategy using boric acid and melamine as starting materials, and Co (SO3NH2)2 center dot 4 H2O as a catalyst precursor. Subsequently, novel low-carbon Al2O3-C refractories were prepared via a replacement of the graphite with the as-synthesized rod-like h-BN. When 1 wt% h-BN rods were added to replace graphite, after 3 h coking at 1400 degrees C, the cold modulus of rupture, cold compressive strength, oxidation resistance, and thermal shock resistance of the specimen were increased by 16.4%, 24.8%, 31.2%, and 52.2%, respectively, compared with these of the control specimen. Moreover, the introduction of h-BN rods in the matrix enhanced the non-wetting ability of the refractory with molten slag, thus the rod-like h-BN modified low carbon refractory presented better slag corrosion resistance with reference to the specimen without h-BN rods.