EVALUATION OF FLUORESCENT DYES FOR EPOXY IMPREGNATION OF POROUS CERAMICS

Eight different commercially available fluorescent dyes (fluorochromes ) were tested for suitability for use in low-viscosity epoxy resin. Dy es were compared based on solubility in different solvents and epoxy r esin and a numerical criterion for each dye's fluorochromicity. The tw o best dyes, based upon the brightness of each dye after illumination by a UV source, were Hostasol Red GG and Hostasol Yellow 3G. These two dyes in epoxy resin were used to visualize impregnation and remnant p orosity in porous superconductor ceramic pellets. The impregnant was e ither cured epoxy or a low melting point alloy.