Effect of (Cr0.8V0.2)2(C,N) addition on microstructure and mechanical properties of WC–8Co cemented carbides

• (Cr0.8 V0.2)(C,N) powders were firstly used as grain refiner in cemented carbides.
• Contrast between (Cr0.8 V0.2)(C,N), (Cr,V)C and Cr3C2 /VC on properties and microstructure of cemented was investigated.

In this work, to inhibit the growth of WC grains during sintering, (Cr0.8V0.2)2(C,N) solid solution powders were firstly used as inhibitor. The effects of (Cr0.8V0.2)2(C,N) on the microstructure and mechanical properties of WC–8wt%Co cemented carbides were systemically investigated. Microstructural analysis revealed that the WC grain growth could be more strongly limited by the combined addition of (Cr0.8V0.2)2(C,N) powder as compared with (Cr,20V)3C2 and Cr3C2/VC additions., (Cr0.8V0.2)2(C,N) also can improve the bending strength and hardness of WC–8Co cemented carbides. WC–8Co cemented carbides with 0.5 wt.% (Cr0.8V0.2)2(C,N) powders have optimum mechanical properties which the bending strength, hardness and toughness are 3800 MPa,1690 HV30 and 9.9 MPam1/2, respectively.