Atomic Delocalization in Solar Flare Heavy-Ion Tracks and Its Impact on the Plastic Deformation of CE-5 Lunar Soil

Abstract Understanding the impact of space weathering on the mechanical properties of materials can provide strong implications for the exploration of the space including the building of a permanent base on airless planets. By examining the structure of solar flare tracks, which exist prevalently in lunar soils returned by Chang’e-5 mission, we revealed that the solar flare tracks are nanosized tubular defects where the silicon and oxygen atoms are delocalized. They are created by implantations of particles with atomic number larger than vanadium. The solar flare tracks first function as dislocation sources and act as strong hindrance for dislocation motions subsequently, resulting in dislocation multiplication and strain hardening. These changes make the mechanical properties of lunar soil significantly distinct from its counterpart residing on the Earth.