Zirconium diboride properties

Uses. In spite of unique properties, there are few commercial appUcations for monolithic shapes of borides. They are used for resistance-heated boats (with boron nitride), for aluminum evaporation, and for sliding electrical contacts. There are a number of potential uses ia the control and handling of molten metals and slags where corrosion and erosion resistance are important. Titanium diboride and zirconium diboride are potential cathodes for the aluminum Hall cells (see Aluminum and aluminum alloys). Lanthanum hexaboride and cerium hexaboride are particularly useful as cathodes ia electronic devices because of their high thermal emissivities, low work functions, and resistance to poisoning. 

Titanium diboride exhibits a high melting point, electronic conductivity, wetability by molten aluminum, and a resistance towards chemical attack of aluminum and molten fluorides. Due to these properties, TiB2 is considered to be the most promising material for inert cathodes in aluminum electrolysis. Also zirconium diboride belongs to the category of promising constructive materials due to its favorable properties. 

F. Monteverde, A. Bellosi, et al.. Processing and Properties of Zirconium Diboride-based Composites, J. European Ceram. Soc., 22 3, 279-288 (2002). 

F. Monteverde, S. Guicciardi, et al.. Advances in Microstructure and Mechanical Properties of Zirconium Diboride Based Ceramics, Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process., 346(1-21,310-319(2003). 

Ceramic borides, carbides and nitrides are characterized by high melting points, chemical inertness and relatively good oxidation resistance in extreme environments, such as conditions experienced during reentry. This family of ceramic materials has come to be known as Ultra High Temperature Ceramics (UHTCs). Some of the earliest work on UHTCs was conducted by the Air Force in the 1960 s and 1970 s. Since then, work has continued sporadically and has primarily been funded by NASA, the Navy and the Air Force. This article summarizes some of the early works, with a focus on hafnium diboride and zirconium diboride-based compositions. These works focused on identifying additives, such as SiC, to improve mechanical or thermal properties, and/or to improve oxidation resistance in extreme environments at temperatures greater than 2000°C. 

Effect of Electrolysis Parameters on the Coating Composition and Properties during Electrodeposition of TVingsten Carbides and Zirconium Diborides... 

S. Zhu, W.G. Fahrenholtz and G.E. Hilmas Influence of silicon carbide particle size on the microstructure and mechanical properties of zirconium diboride-silicon carbide ceramics. Journal of the European Ceramic Society 27,2077-2083 (2007). 

F. Monteverde, S. Guicciardi and A. Bellosi Advances in microstructure and mechanical properties of zirconium diboride based ceramics. Materials Science and Engineering A 346,310-319(2003). 

ZrB2 (zirconium diboride) possesses excellent corrosion resistance. This property makes it useful for making crucibles to contain molten metals. In aluminum production, it is used as the cathode material. Aluminum is produced by molten salt electrolysis. 

DD Radev, M Marinov. Properties of titanium and zirconium diborides obtained by self-propagated high-temperature synthesis. J Alloys Compos 244 48, 1996. 

Fabrication, Microstructure, and Properties of Zirconium Diboride Matrix Ceramic.354... 

Monteverde, E, Bellosi, A., Guicciardi, S. (2002). Processing and properties of zirconium diboride-based composites. Journal of the European Ceramic Society, 22, 279-288. doi 10.1016/80955-2219(01)00284-9. 

Snydera, A., Boa, Z., Hodson, S., Fisherb, T., Stanciu, L. (2012). The effect of heating rate and composition on the properties of spark plasma sintered zirconium diboride based composites. Materials Science and Engineering A, 538, 98-102. doi 10.1016/j.msea.2012.01.019. 

Wang, H., Wang, C. A., Yao, X., Fang, D. (2007). Processing and mechanical properties of zirconium diboride-based ceramics prepared by sparkplasma sintering. Journal of the American Ceramic Society, 90(1), 1992-1997. doi 10.1111/j.l551-2916.2007.01665.x. 

Zhou, S. B., Wang, Z., Sun, X., Han, J. C. (2010). Microstructure, mechanical properties and thermal shock resistance of zirconium diboride containing silicon carbide ceramic toughened by carbon black. Materials Chemistry and Physics, 722(2-3), 470 73. doi 10.1016/j.matchemphys.2010.03.028. 

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