Mechanical and thermal properties of carbon nanotube/aluminum composites consolidated by spark plasma sintering

Aluminum matrix composites reinforced with 0–5.0 wt.% multi-walled carbon nanotubes (MWNTs) were produced by spark plasma sintering (SPS). The composites with ⩽1.0 wt.% MWNTs additions had higher thermal conductivity than the pure aluminum produced by the same SPS processing. The MWNTs/Al composites exhibited the maximum thermal conductivity of 199 W/m/K at 0.5 wt.% MWNTs. The enhancement of thermal conductivity is supported by the measured tensile strength. The MWNTs/Al composites exhibited the maximum tensile strength of 130 MPa also at 0.5 wt.% MWNTs. The contribution of carbon nanotubes to thermal conductivity of the composites was demonstrated by theoretical analysis. The results show that MWNTs reinforced aluminum matrix composite is a potential material for high thermal conductivity applications.

► MWNTs/Al composites have been produced by spark plasma sintering.
► The highest tensile strength of 130 MPa was achieved at 0.5 wt.% MWNTs.
► The highest thermal conductivity of 199 W/m/K was achieved at 0.5 wt.% MWNTs.
► The enhanced mechanical and thermal properties are due to MWNTs bridging.