Measurement of Dynamic Elastic Modulus and Poisson's Ratio of Chemically Strengthened Glass

Materials (Basel). 2020 Dec 10;13(24):5644. doi: 10.3390/ma13245644.

Abstract

Glass with strong durability and transparency has been in the spotlight in various fields, including displays. Elastic and shear moduli and Poisson's ratio are important properties of glasses. The purpose of this study is to evaluate the change in mechanical properties, such as the dynamic elastic modulus and Poisson's ratio, with respect to the chemical strengthening time of glass for display applications, as measured by static and dynamic methods. The basic measurement principle of the dynamic method is to measure acoustic speed or resonant frequency using an ultrasonic generator. The mechanical properties of both non-strengthened and chemically strengthened glasses were investigated. It was found that the strength of the chemically strengthened glass decreased when chemical strengthening time increased. Chemical strengthening increased the bending strength and decreased the elastic modulus due to the introduction of compressive residual stress at the surface.

Keywords: dynamic elastic modulus; glass; impulse excitation technique; ion exchange; ultrasonic pulse echo overlap technique.