Micro-Mechanism of Interfacial Separation and Slippage of Graphene/Aluminum Nanolaminated Composites.

Jia-Qi Zhu,Qing-Sheng Yang,Kun-Kun Fu,Xiao-Qiao He

doi:10.3390/nano8121046

Abstract

Due to their excellent properties and two-dimensional geometry, graphenes (Grs) have been widely used as reinforced fillers in graphene/aluminum nanolaminated composite (GANC). The separation and slippage behavior of the GANC is highly dependent on the interfacial properties between Gr and aluminum (Al). In this study, two interfacial failures of GANCs, i.e., pull-up failure and pull-out failure, were investigated using a molecular dynamics (MD) method. The effects of the crystal orientation of single-crystal Al component and the geometry of the Gr component on the normal and shear interfacial properties of the GANC were examined. It was evident that the interfacial pull-up resistance resulted from the atomic forces of all the atoms at the interface, whereas the interfacial shear force during pull-out stems from the atomic forces of the atoms at the crack tip. In addition, the studies revealed that the interface bonding strength between the Gr and Al was sensitive to both the crystal orientation of the Al and the environmental temperature. Finally, the cohesive law was used to describe the interfacial behavior of the Gr and Al, providing the interfacial data for the finite element modeling of composites with Gr and Al interface.

Highlights

Metal matrix composites (MMCs) reinforced by some carbon nanomaterials, such as carbon nanotube (CNT), graphene (Gr) and their derivatives [1,2,3,4,5], have been extensively used in applications such as aerospace and electronic packaging
Experiments and molecular dynamics (MD) simulations of CNT pull-out in a palladium matrix were conducted by Hartmann et al [14,15], revealing that pull-out force is dependent on the diameter of the CNT and the defect inside the CNT
A representative volume element (RVE) model was taken from the graphene/aluminum nanolaminated composite (GANC) to setup an MD

Summary

Introduction

Metal matrix composites (MMCs) reinforced by some carbon nanomaterials, such as carbon nanotube (CNT), graphene (Gr) and their derivatives [1,2,3,4,5], have been extensively used in applications such as aerospace and electronic packaging. Over the past few years, the shear interfacial properties between carbon nanomaterial (e.g., CNT) and metal or polymer matrix have been widely examined by pull-out loading [7,8,9,10,11,12]. Extensive studies have been presented focusing on the Gr/metal MMCs using experimental method and MD simulation, the normal interfacial behavior of the Gr/metal MMCs is still unclear, especially for lightweight graphene/Al nanolaminated composite (GANC). The interfacial separation and slippage behavior between Gr and Al in GANCs were investigated using an MD method in an effort to provide useful insights into the binding ability between Gr and Al and the mechanism of load transfer during failure process. The present work, based on a simplified model, is of great importance to the further research in modeling and exploring the realistic interfacial issue of the GANC

MD Models

MD Simulation Method

Normal Interfacial Behavior by Pull-Up Simulation

Conclusions