Effect of Cr₃C₂ and VC on the Mechanical and Structural Properties of Sintered WC-10wt%Co Nano Powders

Morteza Mahmoodan, Hamed Aliakbarzadeh, Farzad Shahri

Metallurgy and Material Engineering, Iran University of Industries and Mines (IUIM), Tehran, Iran.
Metallurgy and Material Engineering, Islamic Azad University Saveh Branch, Saveh, Iran.
Metallurgy and Material Engineering, Maham Research Center, Tehran, Iran.

DOI: 10.4236/wjnse.2013.32005                

Abstract

The effect of addition of metallic carbides Cr₃C₂ and Cr₃C₂ + VC on structure and mechanical properties of WC-10 wt% Co nanocomposites have been studied. After preparing and compacting of the powders under pressure of 200 MPa, the samples were sintered at temperatures of 1370°C, 1410°C and 1450°C for 1 hour. Microstructural examinations by SEM show that the average grain size obtained for Cr₃C₂ + VC added alloys reduced 50 percent and also grain size distribution was narrower compared to those samples without grain growth inhibitors. Furthermore, co-addition of Cr₃C₂ and VC rise to a higher Vickers hardness and fracture toughness of the sintered alloys at 1410°C.

Keywords

WC-10Co; Cr₃C₂; VC; Hardness; Fracture Toughness; Grain Size

Conflicts of Interest

The authors declare no conflicts of interest.

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