Reversed Ballistics on Soda Lime Glass
Abstract
The response of soda-lime glass and other similar glasses to impact loading has attracted much attention owing to the discovery of the so-called failure waves in glasses and polycrystalline ceramics. Planar plate-impact and symmetric Taylor tests, in combination with high-speed optical imaging, reveal that when certain glasses are subjected to normal impact above a threshold compressive stress, a "failure front" develops at the impact face and moves from the impact plane at speeds of approximately one-third the longitudinal wave speed in the intact glass.In the proposed investigation a series of reversed ballistics experiments will be conducted to extend our understanding of failure kinetics and overall penetration resistance of soda-lime glass against metallic rod penetrators. The cylindrical soda-lime glass targets will be launched against stationary pure tantalum penetrator rods. In addition, during ballistic impact, the phenomena of dwell and interface defeat at the target interface continue to be of interest to the science community as these mechanisms can provide significant improvement to the protective efficacy of transparent armor systems. Accordingly, the phenomena of interface defeat and the transition velocity from dwell to penetration will also be a topic of special interest to the present study.In the first year of this two-year proposed project, a state-of-the-art experimental capability will be developed to conduct reverse ballistics experiments on cylindrical targets in the impact velocity range 0.5 km/s to 2.5 km/s using the light powder gun facility at the Institute for Shock Physics (ISP), Washington State University. Using this new capability, we plan to investigatedynamic failure and penetration resistance of soda-lime glass against pure tantalum and gold penetrator rods. The reversed ballistic mode is particularly attractive since targets deployed by a sabot, using laboratory scale launch tubes, are sufficiently small such that multiple flash X-rays can be employed to obtain precise position versus time history of the penetrator rod inside the targetsduring the penetration event. Moreover, in-situ high resolution time-resolved optical imaging can be used to provide critical information on nucleation and propagation of the failure-front in the impacted SL glass targets.The Institute for Shock Physics is well equipped with the necessary launch tube drivers to conduct the proposed experiments. A 2022 DURIP proposal will be submitted by the PI to upgrade the Flash X-ray diagnostic capability available at the ISP. The engineering staff at the ISP will assist the PI on carrying out the proposed engineering design tasks and executing the ballistic experiments.The proposed research addresses Navys current and future specific interests in better understanding the impact and shock response of glassy materials under extreme (ballistic) loading conditions. In particular, the proposed work will help provide fundamental insights intothe scientific phenomena associated with ballistic impact events on transparent armor (window) materials. Special emphasis is placed on developing novel experiments with state-of-the-art in-situ diagnostics that will help inform development of more robust constitutive models for material failure andmultiscale computational methods at relevant temporal and spatial scales. Another important outcome of the proposed work to the US Navy will be its direct contribution to the critical database on the response of strategic materials in extreme dynamic environmentsths, leading to enhanced protection of naval infrastructure, vehicles, vessels, and personnel.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 09, 2021
- Source ID
- N000142112538
Entities
People
- Vikas Prakash
Organizations
- Office of Naval Research
- United States Navy
- Washington State University