Strengthening behavior of composite containing discontinuous reinforcement is strongly related with load transfer at the reinforcement-matrix interface. We selected multi-walled carbon nanotube (MWCNT) and few-layer graphene (FLG) as a reinforcing agent. By varying a volume fraction of the reinforcement, aluminum (Al) matrix composites were produced by a powder metallurgy method. Uniform dispersion and uniaxial alignment of MWCNT and FLG in the Al matrix are evidenced by high-resolution transmission electron microscope analysis. Although the reinforcements have a similar molecular structure, FLG has a 12.8 times larger specific surface area per volume more than MWCNT due to geometric difference. Therefore an increment of a yield stress versus a reinforcement volume fraction for FLG shows 3.5 times higher than that of MWCNT Consequently, for both reinforcements, the composite strength proportionally increases with the specific surface area on the composite, and the composites containing 0.7 vol% FLG exhibit 440 MPa of tensile strength.
Bibliographical noteFunding Information:
This research was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Education ( 2013R1A2A2A01068931 ). H.J. Choi acknowledges the support of the NRF funded by the Science, ICT & Future Planning (MSIP) ( 2013R1A1A3005759 and 2013K1A4A3055679 ).
All Science Journal Classification (ASJC) codes
- Materials Science(all)