Quasi-static and dynamic flexural behavior of annealed and chemically strengthened aluminosilicate glass with notch defects

Three-point bending tests on unstrengthened annealed glass (AG) and chemically strengthened glass (CSG) were conducted under quasi-static and dynamic loading conditions to assess the flexural strength and failure characteristics with the help of a high-speed camera. The flexural strength of CSG was higher than AG due to residual compressive stress. At higher loading speed, the flexural strength of both AG and CSG specimens was increased and the strength dispersion was decreased. Additionally, the flexural strength of AG and CSG notched specimens were explored and results revealed that the flexural strength decreased remarkably due to stress concentration effect. However, the flexural strength of CSG specimens was still much higher than AG specimens for the same notch depth. Numerical simulation of the notched CSG specimen showed that the stress near the notch region redistributes due to the strengthened layer, making it under compression before loading. Also, fractography analysis was discussed to characterize the crack pattern and deformation mechanism.