On-line version ISSN 1678-4553
CINTRA, G. B. et al. In-situ spinelization and thermal shock performance of refractory castables. Cerâmica [online]. 2008, vol.54, n.331, pp. 287-295. ISSN 1678-4553. http://dx.doi.org/10.1590/S0366-69132008000300004.
The steel ladle working life is directly related with the refractory lining performance. Considering the great corrosion promoted by basic slags in the secondary steelmaking industry, the use of a high quality material is essential. The corrosion resistance is attained by the use of alumina-magnesia refractory castables, as the in-situ spinel formation leads to a better chemical performance. The steel ladles are also subjected to abrupt temperature changes, due to heating and cooling cycles. Therefore, the thermal shock evaluation is of utmost importance to a proper material selection. The objective of this paper is the analysis of the matrix components and its consequences on the thermal shock damage in order to attain the most suitable thermo mechanical solution coupled with a high corrosion resistance, resulting the increase of the life expectancy of a steel ladle. The results presented show that alumina-spinel castables had better performance than alumina-magnesia castables when there is no constraining. The presence of microssilica increased the thermal shock damage, and this may be related to the testing temperature range.
Keywords : refractory castable; spinel; thermal shock.