Abstract:
Under conditions of plasma-chemical synthesis in low-temperature (4000–6000$^\circ$C) nitrogen plasma, ultrafine and nanocrystalline powder compositions VC–Ni and VN–Ni were obtained from mechanical mixtures containing vanadium carbide or nitride with metallic nickel in the ratio 1:1. X-ray studies have shown that the obtained plasma-chemical particles contain vanadium oxycarbides and oxynitrides, metallic nickel, and are also characterized by the presence of oxide phases of the V–O system. Electron microscopic studies of nanocrystalline fractions of VC–Ni and VN–Ni powder compositions using high-resolution transmission electron microscopy visualized the structure of the obtained particles. Using the fast Fourier transform, it was shown that the refractory components and metallic nickel form individual nanometer-scale particles that do not come into contact with each other. A chemical mechanism of the organization of highly dispersed mechanical mixtures V–C–O–Ni and V–N–O–Ni under conditions of quenching processes in a turbulent flow of nitrogen gas proceeding at a speed of 10$^5$$^\circ$C/s has been formulated on the basis of the performed research.
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