# Experimental Study on the Impact Resistance of UHMWPE Flexible Film Against Hypervelocity Particles

## TL;DR

This study explores how thin UHMWPE films resist hypervelocity particle impacts, important for spacecraft shielding.

## Contribution

The study identifies three distinct damage modes in UHMWPE films under hypervelocity impacts and provides quantitative penetration thresholds.

## Key findings

- Three damage modes (plastic craters, fracture-melting craters, perforations) were identified based on impact energy and particle size.
- Quantitative thresholds for penetration were established, such as 2.25 μm Al2O3 at 8.5 km/s.
- The study reveals energy-dissipation mechanisms in UHMWPE films under extreme strain rates.

## Abstract

The increasing threat posed by micrometeoroids and orbital debris to in-orbit spacecraft necessitates the development of lightweight and deformable shielding systems capable of withstanding hypervelocity impacts. Ultra-high-molecular-weight polyethylene (UHMWPE) films, owing to their high specific strength and energy-absorption capacity, present a promising candidate for such applications. However, the hypervelocity impact response of thin, highly oriented UHMWPE films—distinct from bulk plates or composites—remains poorly understood, particularly for micron-scale particles at velocities relevant to space debris (≥8 km/s). In this study, we systematically investigate the impact resistance of 0.1 mm UHMWPE films using a plasma-driven microparticle accelerator and a hypervelocity dust gun to simulate impacts by micron-sized Al2O3 and Fe particles at velocities up to ~8.5 km/s. Through detailed analysis of crater morphology via scanning electron microscopy, we identify three distinct damage modes: plastic-dominated craters (Type I), fracture-melting craters (Type II), and perforations (Type III). These modes are correlated with impact energy and particle size, revealing the material’s transition from large-scale plastic deformation to localized thermal softening and eventual penetration. Crucially, we provide quantitative penetration thresholds (e.g., 2.25 μm Al2O3 at 8.5 km/s) and establish a microstructure-informed damage classification that advances the fundamental understanding of UHMWPE film behavior under extreme strain rates. Our findings not only elucidate the energy-dissipation mechanisms in oriented polymer films but also offer practical guidelines for the design of next-generation, flexible spacecraft shielding systems.