Silicon carbide passive oxidation

At high temperature, silicon carbide exhibits either active or passive oxidation behavior depending on the ambient oxygen potential (65,66). When the partial pressure of oxygen is high, passive oxidation occurs and a protective layer of Si02 is formed on the surface. 

A fresh surface of silicon carbide is thus constandy being exposed to the oxidizing atmosphere. Active oxidation takes place at and below approximately 30 Pa (0.23 mm Hg) oxygen pressure at 1400°C (66). Passive oxidation is determined primarily by the nature and concentration of impurities (67). 

Shimoo, T., Morisada, Y., Okamura, K., (2002), Active-to-passive oxidation transition for polycarbosilane-derived silicon carbide fibers heated in Ar-02 gas mixtures , J. Mater. Sci., 37, 1793-1800. 

Schneider, B., Guette, A., Naslain, R., Cataldi, M., Costecalde, A., 1998), Atheoretical and experimental approach to the active-to-passive transition in the oxidation of silicon carbide , J. Mater. Sci., 33, 535-547. 

A temperature resistant binder is necessary to bond SiC-bricks (carborundum bricks). Clays or other silicates are usually used, the particles being bonded by a glass phase. The bricks must be fired at ca. 1500°C in an oxidizing atmo.sphere to reduce the reduction of bonding clay to silicon and thereby prevent the bricks becoming brittle. The resulting oxidation of silicon carbide is limited by the formation of a passivation layer of Si02 on the SiC particles. 

Medout-Marere, V., Partyka, S., Dutartre, R., et al. (2003). Surface heterogeneity of passively oxidized silicon carbide particles vapor adsorption isotherms. J. Colloid Interface Sci., 262, 309-20. 

A theoretical and experimental approach to the active-to-passive transition in the oxidation of silicon carbide./. Mater, Sci, 33, 535-547. 

T. Narusima, T. Goto and T. Hirai, High-Temperature Passive Oxidation of Chemically Vapor Deposited Silicon Carbide,/. Am. Ceram. Soc., 72, 1386-90 (1989). 

V. Medout-Marbie, S. Partyka, G. Chauveteau, J.M. Douillaid, R. Dutartre, Surface heterogeneity of passively oxidized silicon carbide particles vapor adsorption isotherms. J. Colloid Interface Sci. 262(2), 309-320 (2003). doi 10.1016/S0021-9797(03)00198-X C.J. Van Oss, The Apolar and Polar Properties of Liquid Water tmd Other Condensed-Phase Materials, in Interface Science and Technology, vol 16 (Elsevier, Amsterdam, 2008), pp. 13-30. doi 10.1016/S1573-4285(08)00202-0... 

V. Medout-Marere, A. El Ghzaoui, C. Chamay, J.M. Douillard, G. Chauveteau, S. Partyka, Surface Heterogeneity of Passively Oxidized Silicon Carbide particles Hydrophobic-Hydrophilic partition. J. Colloid Interface Sci. 223(2), 205-214 (2000). doi 10.1006/jcis. 1999.6625 J.M. Douillard, Concerning the thermodynamic consistency of the "Surface Tension Components" equations. J. Colloid Interface Sci. 188(2), 511-515 (1997). doi 10.1006/jcis. 1997. 4768... 

Narushima T, Goto T, Hirai T, High-temperature passive oxidation of chemically vapor deposited silicon carbide , J Am Ceram Soc, 1989 72(8) 1386-1390. 

Nickel K G, The role of condensed silicon monoxide in the active-to-passive oxidation transition of silicon carbide , JEur Ceram Soc, 1992 9 3-8. 

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