Joint Low-Temperature Carbothermic Synthesis of WC-Co Alloy in Vacuum

Abstract:

A new method for obtaining submicron hard alloys based on sintered tungsten carbide with cobalt by joint low-temperature carbothermic synthesis in vacuum has been developed. The compositions of the initial components for the synthesis of powders of the composition WC-6%Co and WC-10%Co are calculated. The main component for the synthesis of submicron tungsten carbide powders is tungsten oxide WO_2.9, obtained by reducing α-tungsten oxide WO₃ in a hydrogen medium at a temperature of 500-550 °C. The powders obtained by synthesis are characterized by high hardness values (up to 94 HRA). Cutting tests of replaceable polyhedral plates made from the obtained powders for processing a heat-resistant alloy have shown satisfactory results. The microstructure of the alloys was analyzed using scanning electron microscopy.

• Periodical: Key Engineering Materials (Volume 941)
• Pages: 135-140
• DOI: https://doi.org/10.4028/p-vd4byt
• Online since: March 2023
• Authors: Aleksandr Valerievich Golub*, Nikita Ivanovich Rumyantsev, Valery N. Tsemenko, Sergey Vladimirovich Ganin
• Keywords: Composite Materials, Hardmetal, Sintering, Synthesis, Tungsten Carbide

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