Hydrocode modelling of hypervelocity impact on brittle materials: Depth of penetration and conchoidal diameter

You are here: Homepage > Search

Hydrocode modelling of hypervelocity impact on brittle materials: Depth of penetration and conchoidal diameter

Taylor, E.A. / Tsembelis, K. / Hayhurst, C.J. / Kay, L. / Burchell, M.J.

The Johnson-Holmquist brittle material model has been implemented into the AUTODYN hydrocode and used for Lagrangian simulations of hypervelocity impact of spherical projectiles onto soda-lime glass targets. A second glass model (based on a shock equation of state and the Mohr-Coulomb strength model) has also been used. Hydrocode simulations using these two models were compared with experimental results. At 5 km s^-1, the Mohr-Coulomb model under-predicted the depth of penetration, whilst adjustment of the Johnson-Holmquist model bulking parameter was required to match the experimental data to the simulation results. Neither model reproduced the conchoidal diameter; a key measured parameter in the analysis of retrieved solar arrays, so two failure models were used to investigate the tensile failure regime. A principal tensile failure stress model, with crack softening, when used with failure stresses between 100 and 150 MPa and varying bulking parameters, reproduced the conchoidal diameter morphology. Empirically-determined, power-law damage equation predictions for the range 5-15 km s^-1 were compared with simulations using both models since no experimental data was available. The power-law velocity dependence of the depth of penetration simulations was found to be significantly lower than the 0.67 predicted by the empirically-determined damage equations.