A method for evaluating a fused-cast-alumina-zirconia-silica refractory for the properties as a furnace material, based on non-luminous object color represented by L*a*b* system as defined in JIS Z8729, which comprises representing the non-luminous object color of the fused-cast-alumina-zirconia-silica refractory by the psychometric lightness (L*) represented by one of coordinates in a three-dimensional color space having a perceptively substantially uniform rate, and/or the chroma index (C*ab=(a*<2>+b*<2>)<1/2>) as calculated from chromaticness indices a* and b* represented by two coordinates in the three-dimensional color space having a perceptively substantially uniform rate; comparing the psychometric lightness (L*) and/or the chroma index (C*ab) with preliminarily set ranges thereof, respectively; and judging that the fused-cast-alumina-zirconia-silica refractory is suitable as a furnace material when the psychometric lightness (L*) and/or the chroma index (C*ab) are within the set ranges.
Fused-cast-alumina-zirconia-silica refractory and method for evaluating it