| In this paper, we discussed the preparation of the Ti (C, N) compound and the relevant materials by combustion synthesis, mechanical alloying and spark plasma sintering, adopting the solid carbon and nitrogen precursor (C0.36N0.64) powder as the carbon and nitrogen source. We also studied the formation mechanism of the material and its basic physical and chemical properties in a systematic way.Using melamine pyrolysis method, a solid state carbon and nitrogen (C0.36N0.64) powders with a turbostratic graphite structure were obtained, which had a composition of36.0at%C,63.5at%N and0.5at%H. Thermal analysis indicated that the decomposition temperature of this carbon and nitrogen powders were between600-800℃. Therefore, these carbon-nitrogen powders are the ideal nitrogen and carbon sources for the preparation of Ti (C, N).Applying Ti and (C0.36N0.64) powders as raw materials, we explored the feasibility of synthesizing Ti (C, N) compound by thermal explosion reaction. The result showed that the content of Ti (C, N) was low in the resulting product. Analysis considered that the thermal explosion reaction rate was low, and the reaction system was in the open space, leading to a serious volatilization of the (C0.36N0.64) powder, resulting in the less Ti (C, N) in the composition. Utilizing the secondary thermal explosion process that formed during the chemical furnace method, it may promote the formation of Ti (C, N). The main phases of the obtained synthetic products were Ti (C, N) and TiN.The powder of the pure phase Ti (C0.30N0.70) compound was successfully prepared, utilizing the self-propagating high-temperature reaction (SHS), with Ti/Co.36No.64as the raw material. The average particle size of the powder was3μm. The synthetic mechanism of the Ti (C, N) compound was studied systematically by quenching technique. The results showed that before the decomposition of Co.36No.64powder occurred, it had already reacted with Ti in a solid-solid reaction, and formed a small amount of TiN and TiC. As the temperature increasing, Co.36No.64powder decomposed to gases such as N2and C2N2, and then Ti reacted with N2and formed TiN and Ti2N. During this process, a considerable amount of heat were released, prompting a large amount of Ti reacted with C2N2, formed Ti (C, N). Along with the formed TiN and Ti2N, a direct reaction with Co.36No.64powder took place. Eventually the pure phase of Ti (C0.30N0.70) formed.The two methods SHS and thermal explosion were used respectively to research the reaction processes of the Al/Co.36No.64, V/Co.36No.64and Ti/Al/Co.36No.64systems. SHS studies indicated that the Al/Co.36No.64and V/C0.36N0.64systems could obtain the ternary aluminum, carbon and nitrogen and V(C, N), respectively. The Ti/Al/C0.36N0.64system products were Ti2Al(C, N)-Ti3Al, Ti3Al(C, N)2-TiC and AlN-Ti(C, N), and other complex compounds. To treat the Al/Co.36No.64and Ti/Al/Co.36No.64system by thermal explosion reaction, a main phase of A1N and Ti2Al(C, N)-TiAl in the formed products were achieved, respectively.The Ti (C, N) were prepared by spark plasma sintering (SPS). The results indicated that the synthetic route of Ti (C, N) with SPS was Ti+C0.36N0.64→Ti supersaturated solid solution→TiC+TiN→Ti (C, N).The nano-Ti (C, N) were achieved successfully by mechanical milling method (MA), with Ti/Co.36No.64as raw materials. Using the obtained nano-Ti (C, N) to conduct the SPS sintering, a density of98%fine-grained Ti (C, N) bulk material was obtained at1600℃The mechanical analysis showed the hardness and flexural strength of the material were17GPa and700MPa, respectively.Using C0.36N0.64powder, titanium and aluminum as a binder, a dense composite bulk material, containing20%of the diamond or cubic boron nitride of TiAl-Ti2Al(C,N) were prepared successfully by thermal explosion sintering. The observed micro-morphology indicated that the diamond or cubic boron nitride grains bound with the TiAl-Ti2Al(C,N) base together tightly, which will establish the theoretical foundation for the further development of the new tools of super-hard materials.
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