Study of microstructure and interfaces in an aluminium–C60 composite material

Abstract This work deals with the study of microstructure and interfacial reactions in an aluminium–fullerene (Al/C60) composite produced by pressurized liquid metal infiltration (squeeze casting) of a tap-packed C60 powder preform. The obtained composite shows a homogeneous distribution of C60 crystals in the Al matrix, indicating that the original aggregated crystalline structure of the C60 fullerenes was not disrupted during the composite fabrication process, even though there is evidence of partial sublimation of C60. The C60 crystals are well integrated in the matrix and there is no hint either of porosity or of weak interfacial bonding. At the interface between Al and C60 rod-shaped and hexagonal plate-like phases are occasionally observed by TEM. These phases were identified as Al4C3 by XRD and Raman spectroscopy and were shown to nucleate on very thin layers of amorphous carbon at the surface of the C60 crystals.