| Research Abstract |
Mechanical alloying (MA) of metal-fullerene was studied with a view to produce new metal-carbon composites. M-0.3 mol% C60(C70) (a mixture of 87 vol.% C60 and 13 vol.% C70), where M=AI, Cu, Fe, Ni, Sn, Ti or Zn were mechanically alloyed, In order to check the stability of fullerene molecules under MA condition, effect of ball milling on C60(C70) was also investigated. X-ray diffraction and HRThM observation revealed that the initial fcc structure of solid fullerene structure turned out to be an amorphous structure after a long time milling. Liquid chromatography and infrared absorption mea- surements done on the mechanically milled C60(C70) showed that the C60(C70) molecules were stable at least up to 3600 ks of milling. However, milling results in a reduced fraction of C60 and for the same time, showed the formation of a dimer of C60 and C60 polymer. . After milling C60(C70) with a metal for 720ks, a small fraction of the initial C60(C70) retained its identity in Al- and Zn-C60(C70) systems, whereas the molecular structure of C60(C70) is lost when the metal was Cu, Fe, Ni or Sn. The sintered compacts made from the MA powder of a M-C60(C70) and a M-graphite showed similar hardness in the cases of M=Cu, Fe and Ni. However, the sintered compacts made from an AI-C60(C70) MA powder showed about a 40% increase in hardness compared with that made from an Al-graphite MA powder. While in the case of Zn, the hardness of the sintered compact made from the Zn-C60(C70) MA powder was less than half of that made from a Zn-graphite MA powder. The stability of C60 in a metal after MA was discussed according to which element group the metal belonged to on the periodic table.
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