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Carbon-containing refractory bricks are used extensively in the steel industry worldwide. Since the first generation became commercially available in the 1970’s, their processing, microstructures and properties have been improved dramatically, and the service lives of industrial furnaces have thus been extended substantially. In addition to the work on carboncontaining refractory bricks, much effort has been, and is being, made worldwide towards the development of carbon-containing refractory castables. In this paper, the latest R & D towards new generation carboncontaining refractory bricks as well as carbon-containing refractory castables have been highlighted. In the first part, current techniques used to improve mechanical properties of carbon-containing refractory bricks are summarised. A new concept using a catalytic-growth technique to create insitu oxide nanofibres and/or carbon nanotubes in carbon-containing refractory bricks is introduced. The second part addresses some important technical issues of low carbon carbon-containing refractory bricks. Besides the concern about thermal shock resistance, other new problems arising from the use of nanosized carbon, such as the accelerated MgO-C reaction and carbon oxidation, are discussed. In the final part of the paper, technical difficulties hindering the development of carbon-containing castables as well as measures to overcome them are discussed. A novel molten salt synthesis technique developed recently at Sheffield to prepare high quality carbide coatings on graphite is introduced.

Porous reaction-bonded Si3N4-SiC composites were fabricated by using potassium chloride(KCl) as pore-forming agent. Green bodies with 20% SiC and 30% KCl in mass were subjected to presinter in Ar atmosphere at 1000~1200 and then reaction-sintered. The results indicated that Si3N4-SiC composites which with about 58.5% porosity could be prepared, and the main phase compositions were α-Si3N4 and SiC. After presintered, the porosity of composites had small decrease, but bending strength increased obviously and little amounts of Si2N2O had been found. The distribution of pores of porous ceramics was homogeneous and SiC grains were surrounded by Si3N4 grains and fibres. Lots of needle-like α-Si3N4, especially in the high porosity ceramics, could be observed.

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