Self-propagating high-temperature synthesis of ZrB2 in the system ZrO2-B2O3-Fe2O3-Al

Self-propagating high-temperature synthesis (SHS) has been used to prepare many refractory materials such as carbides, borides, silicides, oxides, hydrides, inter-metallics and complex composites [1, 2]. Zirconium diboride (ZrB2), because of its high melting point, su-perior hardness, low electrical resistance, and inertness to many molten metals and slags, is a strong candidate material for wear parts, cutting tools, nozzles and elec-trodes [3, 4]. Previous work on SHS production of ZrB2 has been based on the synthesis directly from its ele-ments [5, 6]. However, the main disadvantage of SHS is that the products are porous because of the large pores in the original mixture of reactants and because of the large volume change resulting from the transformation of the reactants to the products. Also, volatilization o