Abstract
This study is to assess the effect of temperature and strain rate on the mechanical properties of amorphous polyethylene (PE) based on fully atomistic model. A stochastic constitutive model using data obtained from molecular dynamics (MD) simulations for the material is constructed. Subsequently, a global sensitivity analysis approach is then employed to predict the essential parameters of the mechanical model. The sensitivity indices show that the key parameter affecting Young’s modulus and yield stress is the temperature followed by the strain rate.
Highlights
Due to exceptionally physical and mechanical properties, polymers, which are considered as new class of lightweight materials, are extensively used in the automotive, aerospace industry etc
In order to predict the mechanical properties over a large range of conditions, e.g., temperatures, strain rates, etc., molecular mechanism associated with nanostructure of the polymers must be investigated
Since the computational expense of the fully atomistic model are highly expensive while the computation of the first order and the total effect requests a large number of samples, surrogate models will be employed to replace the mechanical model
Summary
Due to exceptionally physical and mechanical properties, polymers, which are considered as new class of lightweight materials, are extensively used in the automotive, aerospace industry etc. Several studies have been made to gain comprehensive understanding complex mechanical behavior of the materials, especially, temperature and strain rate dependent Young’s modulus and yield stress. Since viscoelastic-plastic behavior is of paramount importance for polymers, the temperature and strain rate dependent mechanical properties such as Young’s modulus, yield stress have been qualitatively examined. The temperature and strain rate were considered as deterministic parameters in previous studies [3]. This may result in an overestimation of the mechanical model. We briefly depict nanoscale model with the fully atomistic structure, force field and the simulations’ results.
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call