A simple penetration model for rigid projectiles against ductile targets is enriched by the introduction of an exponential parameter that extends the validity of the model to projectiles with hemispherical heads. The application of the analysis to various head cases is demonstrated with emphasis on the hemispherical head for which simpler relations are derived and the equation of motion explicitly integrated. Resort to the considerable amount of numerical and experimental penetration data available in the literature allows the rational estimation of the various parameters that characterise the model.
characterisation, ductile target, hemispherical head, modelling, ogival head, penetration, rigid projectile.
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