In following are presented the characterization results of nanostructured hybrid composites using alumina matrix reinforced with nanostructured particles of Ni, Ti and soot. The soot used in this work is the byproduct from the synthesis of Carbon Nanotubes (CNT) or fullerene and contains traces (>1wt%) of either CNT or fullerene. Ni and Ti are used in this work for their inherent catalytic ability for heterogeneous nucleation of carbon nanostructures (nanotubes, fullerenes). The hybrid composites are produced by a combination of methods including mechanical milling, sonication, and Spark Plasma Sintering (SPS). Mechanical milling is conducted in high energy mills, the milled and as manufactured powders are sonicated to assure their dispersion, homogeneity and promote percolation of the components during sintering. Mechanical milling and SPS have positive effects to promote the synthesis of different carbon nanoparticles. For instance, it is observed that mechanical milling of fullerene soot sponsors the synthesis of nanostructured diamond particles and using SPS can be synthesized diamond too and fullerene. Although, it is important to notice that SPS conditions are critical to the amount and type of synthesized particles. The use of CNT soot sponsors porosity, hence lower density resulting in an ideal material for membrane and porous media applications. The results of characterization (X-Ray diffraction, electron microscopy (scanning and transmission)) and the mechanical properties (Vickers microhardness) are discussed accordingly.

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Different C phases have been developed by mechanical milling, conventional heat treatments and Spark Plasma Sintering of C soot and transition metals (Fe or Ni). Transition metals are known to catalyze the development of different C phases. The energy input involved in such a processing method has been used to develop composite and ceramic materials made of transition metals and fullerenes and C soot. The as milled samples as well as the sintered composites show various dispersions of diamonds, fullerenes, carbon nanotubes, graphitic carbon, graphenes, among other nanostructures. Thus milling, heat treatment or sintering of quasi-amorphous carbon nanostructures with different transition metals under various conditions can be a simple route to synthesize the above mentioned phases in solid state. Results of electron (scanning and transmission) microscopy, Raman spectroscopy, XRD and nanohardness are presented and discussed accordingly.