Quasistatic to hypervelocity impactor loading of glass: autodyn hydrocode and static testing configurations

Hypervelocity impact on glass leads to damage which involves both high pressure fluid dynamics (forming the “primary” crater) and comparatively low strain rate damage leading to spallation and extended platelet formation (conchoidal fracture). Conchoidal fracture may extend to much larger volumes than the primary crater and subsequently remove most or all of the primary crater. Understanding and modelling thus calls for knowledge of the equation of state, strength limits (both compressive and tensile) and, especially, crack propagation. We examine how a single improved hydrocode with Johnson Holmquist implementation in 2D and 3D can mimic both extremes of the impact process and look at how static test results compare to the hydrocode during the (conchoidal) stress relief by crack propagation at times very much greater than the final primary cratering phase.