中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 34 No. 2 February 2024 |
(1. Institute of Metallurgy and Materials Science, Russian Academy of Sciences, Moscow 119334, Leninsky prospect 49, Russian;
2. Federal Scientific Research Center “Crystallography and Photonics”, Russian Academy of Sciences, Moscow 119334, Leninsky prospect 59, Russian)
Abstract:The possibility to obtain composite micropowders of the W-Cu system with spherical particles having sub-microscale/nanoscale internal structure was confirmed and studied using the complex multistage approach. Composite W-Cu nanoparticles with core–shell structure (W cores and Cu shells) were produced in plasmochemical synthesis in the first stage. Further spray-drying of the aqueous suspension of the W-Cu nanopowder with sucrose enabled the formation of 25-63 μm microgranules with a yield of 50%. The last step was the treatment of the nanopowder microgranules by a thermal plasma jet, which ensured the production of dense spherical W-Cu particles. The final powder had a spheroidization degree of 90%-95%, a bulk density of up to 8.1 g/cm3 and a flowability of 12 s/50 g. The contents of impurities in the resulting spherical micropowder were 0.7 wt.% O, 0.02-0.2 wt.% C and 0.03-0.05 wt.% H.
Key words: W-Cu composites; plasmochemical synthesis; granulation; plasma spheroidization; nanoparticles; microgranules; micropowders