7th International Conference on Matter and Radiation at Extremes (ICMRE2024)

In this paper, with the help of molecular dynamics, six loading velocities of 0.1 km/s, 0.3 km/s, 0.5 km/s, 1.0 km/s, 1.5 km/s and 2.5 km/s are selected to simulate the shock loading of textured nanotwin Cu under three different loading directions of 0°, 45° and 90°. It is found that when the impact velocity is higher than 0.3 km/s, the sample will be destroyed, and the sample has obvious anisotropy during damage process. The damage mechanism is different under different loading directions. In the 0° and 45° unloading, the voids mainly nucleate and grow on the grain boundary, and finally fracture along the grain boundary. Under 90° unloading, the voids mainly nucleate and grow on the twin boundary, and fracture form along the twin boundary, some voids nucleate and grow up inside the twin. With the increase of the impact velocity, the wave profiles difference gradually decreases under different loading direction. The spall strength of textured nanotwin Cu increases gradually with the increase of impact velocity, and the highest spalling strength is about 14.5 GPa at 2.5 km/s impact. Compared with the three loading directions, the spalling strength is the highest under 45° loading.
 

Nanotwin Cu, Shock loading, Anisotropy, Spallation, Texture