Influence of Molten KNO3 Flow Conditions on Mechanical Properties during Fabrication of Chemically-Toughened Glass

  • Kim, Dong-Hwan (Korea Institute of Ceramic Engineering & Technology (KICET)) ;
  • Maeng, Jee-Hun (Korea Institute of Ceramic Engineering & Technology (KICET)) ;
  • Kim, Dami (Korea Institute of Ceramic Engineering & Technology (KICET)) ;
  • Choi, Sung-Churl (Division of Materials Science and Engineering, Hanyang University) ;
  • Kim, Hyeong-Jun (Korea Institute of Ceramic Engineering & Technology (KICET))
  • Published : 2015.03.31


In this study, we examined the influence of molten $KNO_3$ flow on mechanical properties and their deviation when a chemical toughening process was applied to soda lime silicate glass ($Na_2O-CaO-SiO_2$). $KNO_3$ melt flow was controlled using three methods: (1) glass tray rotation, (2) impeller stirring, and (3) natural convection. DOL and hardness were found to be enhanced by tray rotation because this rotation was able to maintain the concentration around the glass surface, in contrast to other methods. However, there did not appear to be a statistically significant difference in the 3-point bending strength for the three flow conditions due to the ground edge condition.


Ion exchange;Chemically-strengthened glass melt flow;Deviation;Soda lime silicate glass


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