Hypervelocity impacts in tungsten

/images/nuclfusion22.png — A representative impact (journal cover).

/images/nuclfusion22_figure.png — A 2 nm W particle impacting a W single crystal at 2 km/s (5, 20, 100 ps); CNA and dislocation analysis.

A 2 nm W cube impacting a W single-crystal target at 3.5 km/s (100 ps): crater creation and damage.

The same 3.5 km/s impact in an isometric view.

Sputtered atoms at an impact velocity of 5 km/s, colored by kinetic energy (blue low, red high).

Combined processes side by side: crater volume, total dislocation length, and sputtered atoms.

Crater detail with real-time plots of total dislocation length, kinetic energy, and crater volume.

Work by Alberto Fraile, Prashant Dwivedi, Giovanni Bonny, and Tomas Polcar at the Czech Technical University (Prague), Bangor University (UK), and the Nuclear Materials Science Institute (Belgium).

The atomistic mechanisms of damage initiation during high-velocity impacts (up to 9 km/s, kinetic energies up to 200 keV) of tungsten projectiles on a tungsten surface were investigated with parallel MD simulations of up to 40 million atoms. Different stages of penetration — implantation, crater size and volume, sputtered atoms, and dislocations — were analyzed. The crater volume grows linearly with kinetic energy, while the total dislocation length depends on the impactor size but not on the interatomic potential used. All visualizations were performed with OVITO.

Related publications

Analysis of hypervelocity impacts: the tungsten case, A. Fraile, P. Dwivedi, G. Bonny, and T. Polcar, Nuclear Fusion 62, 026034 (2022).