Nanopowders (NP) of A1N, Mg_3N_2, Si_3N_4 and TiN have been synthesized in a "cold wall" or "warm wall" plasma chemical reactor (PCR), under the conditions of quasi-equilibrium electric-arc low-temperature plasma (LTP) starting from Al, Mg, Si, Ti powder and N_2, respectively. The degree of nitride-formation is limited by the concentration of atomic nitrogen in the PCR (A1N) and the reagents' residence time in the optimum temperature zone of the PCR (Mg_3N_2, Si_3N_4 and TiN). The NP nitrides synthesized under the conditions of electric-arc LTP have predominantly a spherical shape of the nanoparticles (the condensation follows generally the mechanism: vapours ― liquid ― solid body), while the NP nitrides synthesized under the conditions of HF hot plasma have well-formed microcrystals in the corresponding syngony (the condensation mainly follows the mechanism: vapours ― solid body). Some physico-chemical parameters, like specific surface (dispersity), degree of nitride formation, etc have been studied. Zero porosity of the plasma-chemically synthesized NP nitrides achved the decrease in the hot-molding temperature makes them superior to their conventional analogues with respect to the application in microelectronics and powder metallurgy.
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