Effect of Cr 3 C 2 Addition on Microstructure and Mechanical Properties of WC-CoNiFe Cemented Carbides.

In traditional cemented carbides, Co is mainly used as a binder. Recently, replacing Co with medium- to high-entropy alloys has shown significant improvements in hardness, fracture toughness, high-temperature oxidation resistance, and corrosion resistance, making it a research focus globally. Both the typical grain refiner Cr₃C₂ and medium- to high-entropy alloy binders affect the WC grain size in cemented carbides. This study investigates the synergistic grain refinement mechanism of Cr₃C₂ and medium- to high-entropy alloy binders on WC grains and their impact on the microstructure and mechanical properties of cemented carbides. The results show that increasing the Cr₃C₂ addition refined WC grains in the WC-CoNiFe alloy, increased coercivity, and enhanced hardness, with transverse rupture strength first increasing and then decreasing. The alloy achieved optimal performance at 0.6 wt.%Cr₃C₂, with a hardness of 91.25 HRA and transverse rupture strength of 3883.2 MPa. [ABSTRACT FROM AUTHOR]