Effects of Ion‐Exchange on the Transparent Soda–Lime Silicate Glass‐Ceramics

ABSTRACT Soda–lime silicate (SLS) glass is widely used in commercial applications due to its low cost and adequate mechanical and optical properties. This study combined glass‐ceramic technology with ion‐exchange (IOX) processing to enhance the mechanical performance of 0.15Na 2 O–0.15CaO–0.7SiO 2 SLS glass while maintaining its optical transparency. Transparent SLS glass‐ceramics (SLS‐GCs) were produced by controlling the nucleation and growth of the parent SLS glass, with crystallinity tailored by varying growth times. The resulting SLS‐GCs exhibited surface crystallization, with devitrite (Na 2 Ca 3 Si 6 O 16 ) as the primary crystalline phase and cristobalite (SiO 2 ) as a minor phase. Both the crystalline layer thickness and crystallite size increased with longer growth times. During the subsequent IOX process in a molten KNO 3 bath, Na + to K + exchange primarily occurred in the glassy phase. Although higher crystallinity hindered K + diffusion and resulted in a thinner ion‐exchanged layer, it simultaneously enhanced mechanical strength by increasing hardness and reducing crack probability. In contrast, the elastic moduli decreased with higher crystallinity, likely due to thermal expansion mismatch between the glass matrix and devitrite crystallites. Despite a slight decline in transmittance after crystallization and IOX, all samples retained high optical transparency, demonstrating their potential for applications that demand both mechanical durability and visual clarity.