Ti(C,N)was synthesized with the starting materials of 76.9% titania white and 23.1% carbon black(graphite or activated carbon),or 40% titania white and 60% amylum,with or without 10% NaBr-KCl,dry moulding and carbon embedded firing at 1 300 ℃ and 1 400 ℃ for 3 h,respectively.Phase composition and microstructure of the synthesized Ti(C,N)were analyzed by XRD,SEM and EPMA.Effects of different carbon sources and NaBr-KCl on the synthesis of Ti(C,N)were investigated.The results show that:(1)Ti(C,N)can be synthesized by using carbon black,graphite,activated carbon or amylum as carbon source separately;(2)Additive NaBr-KCl is more favorable for accelerating the carbothermal reduction reaction using carbon black or amylum as carbon source;(3)In the presence of NaBr-KCl,particle size of the synthesized Ti(C,N)is 5-8 μm using carbon black as carbon source fired at 1 300 ℃ for 3 h,while that is only 1-3 μm using graphite,activated carbon or amylum fired at 1 400 ℃ for 3 h.
Cr2O3 has eminent slag corrosion resistance. So, the magnesite-chrome brick is thought as an important refractory material used in RH refining furnace in the process of steel-making around the world. After chrome-bearing sols being prepared by sol-gel method, single sol (Cr(OH)3) and mixed sol (Mg(OH)2-Cr(OH)3) were impregnated into magnesite-chrome bricks by vacuum impregnation. The corrosion resistance of the impregnated bricks to silicon steel slag was studied by porosimetric analysis and fractal dimension calculation. The results showed that the corrosion resistance of impregnated magnesite-chrome brick was better than that of the unimpregnated brick and the brick impregnated by MgSO4 solution, and the one which has surface-treated by Mg(OH)2-Cr(OH)3 sol was the best, mainly because of lower apparent porosity, smaller pores diameter and their smoother inner surface.
