Oral Enhanced mechanical properties of bulk graphene/aluminum composites with a bio-inspired nanolaminated structure

  • Qiang Guo State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University
  • Zan Li State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University
  • Z. Li State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University
  • G. Fan State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University
  • Di Zhang State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University

Abstract

Bulk graphene-reinforced Al matrix composites of various reinforcement concentrations were fabricated via a modifiedpowder metallurgy approach. These composites possess a nanolaminated, brick-and-mortar architecture, where layers of~200nm-thick pure Al platelets are stacked in a staggered arrangement, and are separated by graphene sheets, each containing4-5 graphene monolayers. The composite containing 1.5 vol. % graphene were shown to have an uniaxial tensile strength of302±3MPa, about 50% higher than that of unreinforced Al matrix prepared using the same fabrication route (201±6MPa).Moreover, the composite possess a uniform elongation of 3.4±0.2%, only slightly lower than that of the Al matrix (4.3±0.4%),and have a significantly lower strain hardening capability. Combined with post-mortem and in situ transmission electron microscopic(TEM) analysis, our findings were interpreted in terms of the uniform distribution of graphene in the Al matrix, theeffective load transfer between the graphene sheets and Al platelets, and the interaction between mobile dislocations and thegraphene-Al interfaces.

Abstract

Bulk graphene-reinforced Al matrix composites of various reinforcement concentrations were fabricated via a modifiedpowder metallurgy approach. These composites possess a nanolaminated, brick-and-mortar architecture, where layers of~200nm-thick pure Al platelets are stacked in a staggered arrangement, and are separated by graphene sheets, each containing4-5 graphene monolayers. The composite containing 1.5 vol. % graphene were shown to have an uniaxial tensile strength of302±3MPa, about 50% higher than that of unreinforced Al matrix prepared using the same fabrication route (201±6MPa).Moreover, the composite possess a uniform elongation of 3.4±0.2%, only slightly lower than that of the Al matrix (4.3±0.4%),and have a significantly lower strain hardening capability. Combined with post-mortem and in situ transmission electron microscopic(TEM) analysis, our findings were interpreted in terms of the uniform distribution of graphene in the Al matrix, theeffective load transfer between the graphene sheets and Al platelets, and the interaction between mobile dislocations and thegraphene-Al interfaces.

Published
2018-01-01