W–Ni–Fe nanopowder production processes in thermal plasma are proposed and studied. The processes arise when a pow- dered mixture of corresponding metal oxides is injected into a flow of hydrogen-nitrogen thermal plasma generated inside a DC arc plasma torch.The formation of nanoparticles is carried out as a result of chemical condensation of metals under autoquenching of the high temperature flow inside the reactor with a confined plasma jet. Thermodynamic calculations of equilibrium compositions and characteristics of multicomponent systems W-Ni-Fe-O-H-N have been made.W–Ni–Fe nanopowders have been produced in the experiments and have been studied using TEM, HR–TEM, SEM, ESD, XRD and BET techniques. The final products have been found to be metal composite nanopowders sized from 10 to 150nm. The nanosized metal composites have total oxygen impurity of 1.3–2.7 mass percent. A heat treatment at 800°С in hydrogen reduces the oxygen content up to 0.2 mass percent. The investigation results testify to the possibility of the plas- ma process production of tungsten-based pseudoalloy nanopowders.
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