Experimental determination of Johnson–Cook strength and failure model constants for AA1100H14 aluminum alloy and validation through ballistic impact testing

Abstract

This study presents the experimental determination of Johnson–Cook (JC) strength and failure model constants for AA1100H14 aluminum alloy and their validation through ballistic impact testing. A series of mechanical testing has been performed using an INSTRON UTM for low and a SHPB under high strain-rate conditions, covering a range of strain rates (10⁻⁴ to 190 s⁻¹) and temperatures (25°C to 300°C). The derived JC parameters, capturing alloy's strain hardening, strain-rate sensitivity, and thermal softening behavior, are incorporated in ANSYS/AUTODYN software for simulations. Simulations modeled ballistic impact scenarios with three different nose shapes of projectiles: blunt, conical and ogive, made of 4340 steel impacting AA1100H14 targets under conditions matching experimental testing. The predicted residual velocities and damage mode, such as shear plugging for blunt projectiles and petalling for conical and ogive projectiles, are compared with the outcomes of ballistic tests. The close agreement between simulated and experimental results confirms the accuracy of the experimentally determined JC model parameters, exhibiting their relevance in forecasting the dynamic behavior of AA1100H14 under ballistic impact.