Cluster-induced crater formation

TL;DR

This study uses molecular dynamics simulations to analyze how energetic impacts create craters in materials, revealing that crater volume depends primarily on impact energy scaled to material cohesion, with a consistent efficiency across different materials.

Contribution

It demonstrates that crater volume depends mainly on scaled impact energy and introduces the concept of a universal cratering efficiency applicable to different materials.

Findings

Crater volume scales linearly with impact energy above a threshold.

Crater volume becomes independent of material when scaled by cohesive energy.

Cratering efficiency is approximately 0.5 across materials.

Abstract

Using molecular-dynamics simulation, we study the crater volumes induced by energetic impacts ($v= 1- 250$ km/s) of projectiles containing up to N=1000 atoms. We find that for Lennard-Jones bonded material the crater volume depends solely on the total impact energy $E$. Above a threshold $\Eth$, the volume rises linearly with $E$. Similar results are obtained for metallic materials. By scaling the impact energy $E$ to the target cohesive energy $U$, the crater volumes become independent of the target material. To a first approximation, the crater volume increases in proportion with the available scaled energy, $V=aE/U$. The proportionality factor $a$ is termed the cratering efficiency and assumes values of around 0.5.