Ultrafine high-cobalt hard alloys. II. Connection between mechanical properties and structure

• Published in: Powder metallurgy and metal ceramics 2008-05, Vol.47 (5-6), p.316-323
• Main Authors: Tolochin, A. I., Laptev, A. V., Golovkova, M. E., Koval’chenko, M. S.
• Format: Article
• Language: English
• Subjects: Alloys; Carbides; Ceramics; Cermets; Characterization and Evaluation of Materials; Chemistry and Materials Science; Composites; Compressive strength; Fracture toughness; Glass; Hardness; Materials Science; Mathematical analysis; Mechanical properties; Metallic Materials; Natural Materials; Plastic properties; Powder metallurgy; Refractory and Ceramic Materials; Studies
• ISSN: 1068-1302; 1573-9066
• DOI: 10.1007/s11106-008-9022-6

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.