Achieving better strength-toughness synergy in heterogeneous Cu/Ni/graphene composites: A molecular dynamics simulation

Shuang Zhang, Nan Yang, Yan Tang, Chunfang Ma, Haoran Peng, Guo Chang, Liang Li, Xiang Li, Wei Zhang, Ahmed Elmarakbi, Yongqing Fu, Longlong Dong*, Wangtu Huo*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

The non-wetting nature of copper (Cu) and graphene, coupled with the brittle behavior of graphene, impedes the strength-toughness synergy in graphene-reinforced Cu matrix (Cu/graphene) composites, limiting their practical applications. Benefiting from interface modification engineering and heterogeneous structure strengthening effects, here a novel strengthening and toughening strategy for Cu/graphene composites by introducing a variable-thickness nickel (Ni) modification layer sandwiched between Cu and graphene (Cu/Ni/graphene) was proposed, and the influence of layer thickness-related structural heterogeneity on mechanical properties and underlying deformation mechanisms were investigated via molecular dynamics simulations. The results revealed that an optimal Ni thickness of 2.44 nm within increased Ni layer thickness enhanced the strength-toughness synergy in the Cu/Ni/graphene composites. This was attributed to altered interface structure, stress distribution, and graphene fracture behaviors due to layer thickness-related deformation behavior. In addition to common strengthening mechanisms like graphene load-bearing effect, interface dislocation nucleation, and interface dislocation blockage strengthening, the layer thickness-dependent semi-coherent Cu/Ni and Ni/graphene heterogeneous interface stress strengthening contributed to extra strength enhancement. Furthermore, cooperati deformation behavior among heterogeneous components improved toughness. The interfacial engineering strategy, achieved by tailoring the modification layer thickness, may pave the way for producing nanostructured metallic composites with extraordinary mechanical properties.
Original languageEnglish
Article number109757
Pages (from-to)1-11
Number of pages11
JournalMaterials Today Communications
Volume40
Early online date4 Jul 2024
DOIs
Publication statusE-pub ahead of print - 4 Jul 2024

Cite this