Microstructure Evolution and Deformation Mechanism Comparison of Ta-2.5w and Cu Under Detonation Load

Abstract

The comparison of microstructure evolution of Cu and Ta-2.5W liner during deformation at high temperature and high strain under detonation conditions was studied. The electron backscatter diffraction method (EBSD) was used to statistically observe the microstructure of the liner before and after deformation. Both recycled explosively formed projectile (EFP) shows strong fiber texture and different degrees of recrystallization. The center of the recycled Cu EFP has strong <001> and <111> preferred orientations along the EFP axis, and it shows a gradient change in texture with the strain. Cu EFP has extensive dynamic recrystallization, up to 88%, which is considered to be a traditional dynamic recrystallization nucleation mechanism, the temperature is the main controlling factor in the refinement process. On the contrary, the recycled Ta-2.5W EFP has a strong <101> fiber preferred orientation, and no large-area dynamic recrystallization occurs, large strain deformation is the main factor for the microstructure refinement.

Keywords: tantalum-tungsten alloy, Pure Cu, Explosively Formed Projectile, Dynamic recrystallization, Ultra-high strain rate