THE INFLUENCE OF TEMPERATURE AND CONFINEMENT PRESSURE ON THE DYNAMIC RESPONSE OF DAMAGED BOROSILICATE GLASS

Comminution and pulverization of glass is frequently encountered in the process of projectile penetration on vehicle and building glass windows. During such events, the glass material in front of the penetrator nose will be severely damaged and counteract with further penetration. Both high confinement pressures and high temperatures are expected to take place under these circumstances, and subsequently influence the dynamic mechanical response of damaged glass. The purpose of this study is to investigate such influences on a damaged borosilicate glass with a modified high temperature Kolsky bar setup. Intact glass samples were confined by metal sleeves and loaded to fracture by the primary incident pulse. A secondary incident pulse, which arrived several hundred microseconds later, continued to load on the damaged glass samples under different confinement levels. Non-contact heating technique was also used to investigate the possible temperature effects. The results showed that under dynamic loading conditions, the shear strength of damaged glass increases linearly with confinement pressures. However, the temperature itself does not show any noticeable effect on the shear strength.