Ballistic impact studies of a borosilicate glass

Abstract

The ballistic impact properties of a borosilicate ('pyrex') glass was studied using mild steel rods accelerated using a light gas gun. High-speed photography at sub-microsecond framing rates was used along with schlieren optics to investigate the propagation of elastic shock waves and fracture fronts. Flash X-radiography was used to visualize the deformation of rods as they penetrated the comminuted glass normally. The rod was seen initially to dwell on the surface for at least 3 s creating a Hertzian cone-crack. Later on, between 40 and 60 s, self-sharpening of the projectile was observed as the 'wings' of the heavily deformed front end sheared off. After this event, the front of the rod speeded up.X-rays also showed that the pattern of fissures within the comminuted glass was observed to be very similar shot-to-shot. X-radiography was also used to examine the mechanisms occurring during oblique impact of rods at 45˚. In oblique impact, bending of the rod rather than plastic deformation ('mushrooming') takes on the role of distributing the load over an area larger than that of the original rod diameter. High-speed photography of the rear surface of a glass block on which a fine grid had been placed confirmed that the comminuted glass moved as larger interlocked blocks. The experiments were modelled using the QinetiQ Eulerian hydrocode GRIM making use of the Goldthorpe fracture model. The model was found to predict well the transition from dwell to penetration.

Crack and Shock Propagation Through the Interlayer in Soda Lime Glass Under Detonation Loading

“…The damage pattern is similar to those in other investigations with borosilicate glass . After 5.6 μs of impact, a few cracks begin to nucleate in the direction of the impact point at the interface, gradually grow, and finally integrate as large damage.…”

“…For ceramic, such as SiC, the side faces were polished to a mirror‐like finish so that cracks in the surface were observed by reflected light . Flash X‐ray is a useful instrument in which the X‐ray penetrates low‐density brittle material and creates an image of the material state . This technology is well known.…”

An Introduction to the Properties of Silica Glass in Ballistic Applications

“…I would suggest that the way forward will be to bring in insights from polymer physics (e.g. the Porter–Gould model ), fracture and granular mechanics . Observed differences between glass and metallic shaped charge jets probably lie in what happens as they are formed.…”

Sol-gel synthesis and third-order optical nonlinearity of Au nanoparticles doped monolithic glass

“…To the best of our knowledge, borosilicate glass has low thermal expansion coefficient and high chemical durability, which render borosilicate glass good resistance to thermal shock and breaking [26,27]. The stable physical and chemical properties make borosilicate glass widely used in modern laboratory equipment and optical devices.…”