Localized heat-treating of sanitary-ware ceramics surface imperfections by using lasers

In this thesis, we aimed to develop the fast and economical technique by using lasers (high power diode laser (HPDL) and Nd-YAG) and specially developed low melting white-opaque frit towards the localized heat-treating of surface imperfections by eliminating further firing step. New white opaque frit compositions which have proper thermal coefficient of expansion and low melting capability were developed. Samples which are irradiated by 300 W, 810 nm (CW) high power diode laser (HPDL) and 60 W, 1064 nm Nd-YAG laser were examined by using optical microscopy, scanning electron microscopy (SEM) and energy disperse X-ray analysis (EDX) techniques. Laser parameters were optimized to achieve crack free and non porous surface. The results showed that, glaze defects on sanitary ware ceramics could be localized repaired without micro crack and porosity by using high power diode laser and Nd-YAG laser.