The Distribution of Carbon in a Tungsten–Cobalt Alloy during Heat Treatment in a Gaseous Medium of Carbon Oxides

Autor: Maksim Dvornik, Artem Zaitsev, Elena Mikhailenko, Aleksey Zaytsev
Rok vydání: 2019
Předmět:
Zdroj: Theoretical Foundations of Chemical Engineering. 53:916-920
ISSN: 1608-3431
0040-5795
DOI: 10.1134/s0040579518050081
Popis: Investigations of composition, structure, and hardness of ultrafine-grained solid alloy WC–8Co–0.4VC–0.4Cr3C2 after treatment in a gaseous mixture of CO + CO2 of compacts with a lack of carbon for 50 min at a temperature 650°C on the initial stage of liquid-phase sintering. It was found that at CO content of 72.5% in the gas mixture, conditions are created for replacing the initial carbon deficiency (about 0.3%) and obtaining two-phase ultrafine-grained carbide of stoichiometric composition, in which carbon and hardness are uniformly distributed over the depth of the samples. This alloy has the lowest porosity (2.5%) and the highest hardness (HV1941). It was found that an increase of up to 80% or a decrease of up to 0% of the CO content in a gas mixture leads to the formation of a lack of carbon (1.0%) or an excess of carbon (4.5%) on the surface of the samples. This leads to a significant decrease in hardness. It is shown that the change in the carbon content and hardness in the depth of the samples is much less than on the surface.
Databáze: OpenAIRE
Nepřihlášeným uživatelům se plný text nezobrazuje