A METHOD OF PREDICTING EFFECTIVE INTERFACE PROPERTIES OF POLYMER-METAL HYBRID STRUCTURES BY MOLECULAR DYNAMICS

The interface phase of the Polymer-Metal Hybrid (PMH) structures is formed due to the diffusion of nearby molecular, whose mechanical properties are different from pure metal or polymer, and is possibly the weakest layer. However, it is difficult to measure the interface parameters, such as the thickness and elastic modulus. When the property of PMH structure is predicted by finite element method, it would result in potential simulation errors if the interface is ignored. This study presents a new method to predict the effective interface properties of PMH Structures by Molecular Dynamics (MD) method. The interface formation process in over-molded injection of Polypropylene (PP) on the stamped steel surface was simulated by MD. The effective interface thickness between Iron (Fe) and PP is defined and calculated to be 0.63nm or so and the elastic modulus vertical to the interface is about 6.55GPa. The proposed approach is especially suitable for performance prediction of PMH structure before the physical specimen is manufactured. The predicted results could be utilized in finite element simulation at micro-scale.