Dynamic Response and Microstructure Evolution of Oxygen-Free High-Conductivity Copper Liner in Explosively Formed Projectile

Abstract

The dynamic response and microstructure evolution of oxygen-free high-conductivity copper in a shaped charge liner are investigated through microstructural examination of a soft-recovery EFP. Adiabatic shear bands and voids which is the failure original of copper EFP can be observed in the rear part of the projectile. Numerical simulation results illustrate that the highest plastic strain reaches about 2.9 which can fully accommodate the grains deformation of copper EFP during the formation process at strain rates of the order of 10 4 s −1 . Theoretical calculation results indicate that the highest temperature increase of EFP caused by shock wave and plastic deformation can reach 747K, which is 0.55Tm (where Tm is the melting temperature of copper). The main body of the EFP undergoes completely dynamic recrystallisation, and the average size of the refined grains significantly decreases to approximately 10µm. A slight increase in grain size occurs mainly away from the center and extends towards the head and rear sections of the EFP. During the DRX process, the dislocation movement is believed to be the controlling mechanism significantly refining the microstructure.

Microstructure Evolution and Deformation Mechanism of Tantalum–Tungsten Alloy Liner under Ultra-High Strain Rate by Explosive Detonation

“…Dense Neumann bands consisting of deformation twins have been observed in an Fe EFP by Pappu et al [ 22 ]. The dynamic response and microstructural changes in a Cu EFP were investigated by Liu et al and the results showed that complete DRX occurred in the recovered projectile [ 23 ]. It shows that different microstructures will be generated during the EFP-forming process.…”

Structural Design and Parameter Optimization of Linear Explosive Forming Projectile

“…Wang et al [21] found that the double-layer shaped charge was more conducive to increasing the tip velocity of the jet compared to the ordinary shaped charge. A new MEFP warhead was studied in [22] and tested the dispersion and penetration performance on five steel targets with different supports. In literature [23,24], a special evolvable warhead structure was proposed.…”

A Dynamic Mechanical Analysis of T2 Copper at High Strain Rates

“…T2 copper which is commonly used in shaped charge liner [1][2][3][4] is an important nonferrous metal with superior plasticity. In shaped charge, T2 copper liner is crushed by detonation pressure and forms Jetting penetrator charge (JPC), metal Jet (JET) or explosively-formed projectile (EFP).…”