| About this Abstract |
| Meeting |
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
| Symposium
|
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
| Presentation Title |
Molecular Dynamics Prediction of Strain Rate-Induced Failure Mode Transitions in Crystalline Polyethylene |
| Author(s) |
Nuwan Dewapriya, Sanjib Chowdhury, Joseph Deitzel, John Gillespie |
| On-Site Speaker (Planned) |
Nuwan Dewapriya |
| Abstract Scope |
Under transverse impacts, ultra-high molecular weight polyethylene fibers experience significant axial tension within laminates subjected to high strain rate loading. Employing molecular dynamics simulations, we systematically investigated the impact of strain rate on the axial tensile behavior of polyethylene crystals, considering both pristine crystals and those with chain end defects. With the increase of the strain rate from 10^10 s-1 to 10^13 s-1, pristine polyethylene crystals exhibited a substantial ~60% increase in strength. This enhancement is attributed to higher strain rates hindering the relaxation of individual polymer chains, compelling them to store more energy. Our findings highlight a remarkable increase in the strength of crystals with chain ends when the strain rate escalates from 10^10 s-1 to 10^13 s-1. This notable increase stems primarily from a shift in the failure mode, transitioning from chain end sliding to chain scission. This transition occurs as the loading velocity surpasses the maximum speed at which chains can slide. Notably, our simulations reveal that the influence of strain rate on the progressive failure of crystals initiates at relatively lower strain rates as the molecular weight increases. |
| Proceedings Inclusion? |
Definite: Post-meeting proceedings |