| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advanced Real Time Imaging
|
| Presentation Title |
Ultra-High Strain Rate Impact Response of Polyethylene at Critical Transition Temperatures |
| Author(s) |
Jacob A. Rogers, Aniket Mote, Sidney Davis, Paul Mead, Charles U Pittman, Edwin L Thomas, Justin W Wilkerson, Thomas E Lacy Jr |
| On-Site Speaker (Planned) |
Jacob A. Rogers |
| Abstract Scope |
All spacecraft are at risk of hypervelocity impact from micrometeoroid/orbital debris. Emerging hypersonic weapons pose new threats to military assets. Ultra-high-molecular-weight polyethylene (UHMWPE) and high-density polyethylene (HDPE) show promise as layers in novel, threat-optimized shields due to their high mass-specific energy absorption and tailorability. However, their ultra-high-strain-rate (>10^6 1/s) behavior is understudied, particularly near their glass-transition and melt temperatures. This study examines the effects of initial target temperature, impact velocity, and molecular entanglements on polyethylene’s ultra-high-rate response. UHMWPE and HDPE plates at −120°C-140°C were impacted at km/s velocities by aluminum spheres. PE’s response was driven by a competition between strain rates and molecular relaxation rates. The PE exhibiting the most visco-plastic flow without subsequent fragmentation lost less mass, had smaller perforations, and better absorbed energy, suggesting an optimal number-of-entanglements-per-chain value that maximizes PE energy absorption for given target/impact conditions. This motivates a PE shield made of strain-rate-tuned layers. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Polymers, Characterization, Other |