Modeling deformation and fracture in fused silica under high velocity impact

Nicola Bonora, Andrew Ruggero, G. Ianniti
Techdyn Engineering

Fused silica is a high purity synthetic amorphous silicon dioxide characterized by low thermal expansion coefficient, excellent optical qualities and exceptional transmittance over a wide spectral range. Because of its wide use in the military industry as window material, it may be subjected to high-energy ballistic impacts where post-yield response as well as the strain rate related effects become significant and need to be accounted for in the constitutive modeling. In this work, a procedure for constitutive model assessment is presented. Taylor impact tests and drop weight tests were designed and performed at different impact velocities and strain rates. Numerical simulations were performed using IMPETUS Afea explicit finite element code that offers unique higher order element technology well suited for simulating large deformations and fracture. Model parameters were identified by optimization using modFRONTIER. Model performance was verified for an independent designed impact test.