Impact of high-energy effects on the formation of internal structure in copper particles
A.E. Chesnokov1, A.V. Smirnov1, T.M. Vidyuk1,2
1Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
2Institute of Solid State Chemistry and Mechanochemistry SB RAS, Novosibirsk, Russia
Keywords: mechanical milling, mechanical activation, agglomerated particle, planetary mill, specific surface, plasma torch, spheroidization, dense spherical particle, hollow particle, composite material
Abstract
In the present paper, results of a study of the impact of high-energy effects on the surface morphology and on the formation of the internal structure in PMS-1 copper particles are reported. It is shown that the mechanical milling of the copper powder in a planetary mill leads to the formation of powder agglomerates with a layered structure consisting of numerous deformed ultrafine particles. It is found that the volume of the agglomerated particles involves defects in the form of microcracks and closed micropores with some content of the initial gas. Subsequent treatment of the powder in an argon-helium plasma jet leads to the formation of dense particles, as well as particles with distributed gas volumes or a single cavity. It was found that, as the molten metal interacted with localized gas volumes during the plasma treatment, local oxidation of the material occurred. A dispersion-strengthened structure with copper oxide compounds of a predominantly round shape, ranging in size from tens of nanometers to 7 μm and uniformly distributed over the particle volume, was formed.
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