Development of Nitride-Bonded SiC Refractories by MgO and Nanocomposite (MgO/SiC) Additives

A. A. Nourbakhsh, N. lotfian, P. Asgarian

Islamic Azad University, Department of Materials Science and Engineering, Shahreza Branch, Isfahan/Iran


Volume 9, Issue 4, Pages 106 - 112


In this study the microstructure and properties development of nitride bonded SiC refractories is reported in presence of MgO in laboratory and industrial scales. Also effect of nanocomposite addition (SiC+MgO) which synthesized by magnesiothermal process on optimized samples were studied. The laboratory samples were prepared by mixing, shaping and firing at 1450–1600 °C in control atmosphere furnace. Phase analysis, microscopic observation and mechanical evaluation were taken as criteria for microstructure evolution. Also industrial samples were prepared by optimizing of firing cycle and additives. Then phase analysis, mechanical properties and inhomogeneity on properties of bricks in different part of muffle were investigated. Variation of mechanical properties by using MgO additive could be attributed the microstructure evolution and mainly to liquid phase formation and grain morphology. It was found that the additives, such as MgO could modify the microstructure and influence the mechanical behavior. To extend results to industrial scale, settlement of bricks and modify firing cycle have been investigated to solve inhomogeneity problems. Finally, addition of nanocomposite (MgO+SiC) to optimized samples increased hot modulus of rupture (HMOR), which could be related to better sintering of matrix and formation of β-Si3N4.


N–SiC, nanocomposite, refractory


[1] Schwetz, K.A.; ESK-GmbH: Silicon carbide and its high technology ceramics. Radex Rundschau 1 (1989) 26–38 [2] Kijima, K.: Structure and properties of silicon carbide. Taikabutsu Overseas 15 (1995) 3–12 [3] Brown, R. W.; Steele, D. F.; Oberbanscheidt, H.; Bates, B. H.; Parker, M. O.: Bond developments in silicon carbide blast furnace refractories during the 1980’s. Aachen Proc. (1988) 41–46 [4] Kim, I.S.; Kim, E.H.; Suh, B.G.; Choi Y.S.: Influence of additives on nitridation of metallic silicon in Si3N4-bonded SiC. UNITECR, Japan, (1987) 947–981 [5] Moulson, A.J.: Reaction-bonded silicon nitrides, formation and properties. J. Mater. Sci. (1979) 1017–1051 [6] Messier, D.R.; Riley, F.L.; Brook, R.J.: The /silicon nitride phase transformation. J. Mater. Sci. 13 (1978) 1199–1205 [7] Hannink, H.J.: The development of microstructure in silicon nitride bonded nsilicon carbide. J. Eur. Ceram. Soc. (1995) 415–424 [8] Ruiz, I.R.; Bressiani, A.H.; Bressiani, J.C.: Use of rare earth concentrates as a sialon sintering additives. Mater. Sci. Forum (1999) 141–148 [9] Wötting, G.; Kanika, B.; Ziegler, G.: Microstructural development microstructural characterization and relation to mechanical properties of dense silicon nitride. Int. Conf. on Non-Oxide Technical and Engineering Ceramics, 1985 [10] Ekström, T.; Nygren, M.: SiAlON ceramics. J. Am. Ceram. Soc. 75 (1995) [2] 259–276 [11] Ohashi, M.; Kanzaki, S.; Tabata, H.: Effect of additives on some properties of silicon oxynitride ceramics. J. Mater. Sci 26 (1991) 2608–2614. [12] Lin Yulian; Liu Shengqiu: Manufacture, Properties and Application of Silicon Carbide Refractories. Int. Workshop on Technology and Development of Refractories, China, 1994 [13] Kim, I.S.; Kim, E.H.; Suh, B.G.; Choi, Y.S.: Influence of Additives on Nitridation of Metallic Silicon in Si3N4-bonded SiC. UNITECR, Japan, 1987 [14] Jack, K.H.: Review of sialons and related nitrogen ceramics. J. Mater. Sci 11 (1976) 1135–1158 [15] Nourbaksh, A.A.; Amin, P.; Golestani-Fard, F.: Synthesis of nano composite MgO/Boron carbids by using mesoporous carbon (CMK-1) and SHS process as an antioxidant additive in MgO/C refractories. 57th Int. Colloquium on refractories 2014 [16] Kalbasi, R.J.; Mosaddegh, N.: Synthesis and characterization of poly(4-vinylpyridine)/MCM-48 catalyst for one-pot synthesis of substituted 4H-chromenes. Catal. Commun. 12 (2011) [13] 1231–1237 [17] Shi, Y.; Zhang, F.; Hu, Y.S.; Sun, X.; Zhang, Y.; Lee, H.I.; Chen, L.D.; Stucky, G.: Low-Temperature Pseudomorphic Transformation of Ordered Hierarchical Macro-mesoporous SiO2/C Nanocomposite to SiC via Magnesiothermic Reduction. J. Amer. Chem. 132 (2010) 5552–5553 [18] Zhao, B.; Zhang, H.; Tao, H.; Tan, Z.; Jiao, Z.; Wu,


Göller Verlag GmbH