Physical properties of chemically strengthened thin glass prepared by the spray method using an original KNO3–Al2O3 slurry

In this study, we developed a novel KNO3–Al2O3 slurry for the chemical strengthening of thin glass sheets using a spray process, and investigated the physical properties of the strengthened glass. A 1 μm particle size α-Al2O3 powder is mixed with a KNO3 solution to obtain the novel slurry. Controlling the temperature and duration of the chemical strengthening process effectively tunes the compressive stress and depth of layer. The strengthened thin glass sheet produced in this study exhibits similar strength properties as commercial products. The highest compressive stress (CS) value (868 MPa) is obtained for the sample heated at 400 °C for 1.5 h, and the highest depth of layer value (60 μm) is observed for the sample at 480 °C for 4 h. The strengthened glass shows good hardness and bending strength. The glass sample heated at 400 °C for 1.5 h exhibits the highest hardness (680 HV) and bending strength (630 MPa).