Abstract
The experimental dependences of strength, plastic properties, hardness, and fracture toughness on sintering or pressing temperature for ultrafine alloy WC-41 wt.% Co are presented. The alloy densifies in solid phase and temperature varies from 950 to 1250°C. The dependences of mechanical properties are extreme, excepting fracture toughness. The properties reach their maximum values at 1050 to 1150°C depending on the type of testing. Fracture toughness continuously increases with densification temperature. The highest values of some properties are reached after additional solid-phase annealing. The mechanical properties of ultrafine high-cobalt alloy samples are assessed with the use of structural parameters and empirical equations established for standard hard WC-Co alloys sintered in liquid phase. The calculated and experimental values of properties differ: transverse rupture strength, fracture toughness, and yield strength show higher values, while hardness and compressive strength have lower values as compared with calculated ones.
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Translated from Poroshkovaya Metallurgiya, Vol. 47, No. 5–6 (461), pp. 66–76, 2008.
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Tolochin, A.I., Laptev, A.V., Golovkova, M.E. et al. Ultrafine high-cobalt hard alloys. II. Connection between mechanical properties and structure. Powder Metall Met Ceram 47, 316–323 (2008). https://doi.org/10.1007/s11106-008-9022-6
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DOI: https://doi.org/10.1007/s11106-008-9022-6