Dynamic tensile extrusion of 0.25 and 0.30 caliber hypervelocity particles

Abstract

An electrothermal gun was used to launch 0.25 and 0.30 caliber hemispherical nose aluminum and copper projectiles at velocities from 1000 to 3000 m/s. The projectiles impacted extrusion dies with half angles varying from 10 to 14.5 degrees for dynamic tensile extrusion experiments in the hypervelocity regime. X-radiography, photon doppler velocimetry, and high-speed video were utilized to characterize the resultant hypervelocity particles. ALEGRA simulations of the extrusion process were performed to assess the performance of some material models used in hydrocode and shock physics simulations. The electrothermal gun combined with ALEGRA simulations proved to be a useful tool in characterizing the dynamic tensile extrusion phenomenon at hypervelocity.