Numerical simulation of long rods impacting silicon carbide targets using JH-1 model

The Johnson–Holmquist model for simulating impact and penetration into ceramic and glass materials is commonly used in continuum hydrocodes. There are two forms of the Johnson–Holmquist ceramic model: JH-1 using a segmented linear approximation to the strength envelope with instantaneous failure; JH-2 using a smooth analytic approximation to the strength envelope with damage-induced strength reduction. Both these models are now implemented in the AUTODYN® software. The validation of the JH-1 model is presented in this paper by comparing numerical predictions with experimental data. The failure parameters of the JH-1 model are also validated in the current numerical approach. Good agreement between numerical predictions and experimental measurements is shown for the behavior of silicon carbide in various impact situations. Time histories of particle velocity in compressive and tensile spall plate impact, interface dwell in confined impact, and total penetration depth in oblique impact are used in the comparison. The JH-1 model in AUTODYN is shown to be a powerful numerical tool in the design and analysis of ceramic armor systems.