Effects of Cr3C2 additions on the densification, grain growth and properties of ultrafine WC–11Co composites by spark plasma sintering

The Effect of Cr3C2 and TaC Additives on Microstructure, Hardness and Fracture Toughness of WC-6Co Tool Material Fabricated by Spark Plasma Sintering

“…In turn, the lowest hardness of 1732 HV 30 is noted for WC-6Co-0.3Cr 3 C 2 -0.3TaC and results directly from the porosity which is present in the microstructure (Figure 4h), because the porosity is a critical parameter that affects the hardness of cemented carbides . Similar results were obtained by Sun et al 23 where WC-11Co-xCr 3 C 2 (x = 0.2, 0.4, 0.6, 0.8) ultrafine cemented carbides were fabricated by spark plasma sintering. The highest hardness of 1922 HV 30 and fracture toughness of 14.14 MPa·m 1/2 were noted for an ultrafine WC-11Co-0.6Cr 3 C 2 cemented carbides.…”

Influence of Grain Growth Inhibitors and Powder Size on the Properties of Ultrafine and Nanostructured Cemented Carbides Sintered in Hydrogen

“…The increase of 0.4 wt. % Cr3C2 content considerably reduces the density; when the Cr3C2 content is small the change is slight [8]. The addition of 0.45% Cr3C2 in WC-9Co/1 did not lead to lower density compared to WC-9Co/2, which has only 0.27% VC.…”

“…Their primary task is to preserve the particle size of starting powders in the sintered product, while at the same time influencing the properties of consolidated samples: decreasing density, increasing the value of hardness at room temperature, and also affecting toughness, hardness and creep resistance at elevated temperatures. The combination of VC-Cr 3 C 2 (TaC) proved the most effective due to its high solubility and mobility in the Co binder, which results in an optimal combination of hardness and toughness [7,8]. The process of grain growth in cemented carbides can be characterized as both continuous and discontinuous.…”

“…The process of grain growth in cemented carbides can be characterized as both continuous and discontinuous. Continuous growth is characterized by uniform growth of WC grains, while discontinuous growth characterizes growth of isolated WC grains or groups of WC grains, which grow faster and larger compared to the surrounding grains [8][9][10]. Both growth processes must be avoided in order to obtain satisfactory properties in the sintered products since mechanical properties of ultrafine and nanostructured cemented carbides are directly dependent on the developed microstructure: WC grain size, mean free path of Co and contiguity of WC grains [2,10].…”

MICROSTRUCTURE AND MECHANICAL PROPERTIES OF ULTRAFINE WC/Co CEMENTED CARBIDES WITH CUBIC BORON NITRIDE AND Cr₃C₂ ADDITIONS

“…As a common grain growth inhibitor, Cr 3 C 2 not only has high solubility in Co solutions but also has a low eutectic temperature in Co systems. Therefore, Cr 3 C 2 is particularly appropriate as a grain growth inhibitor in CBN-WC/Co cemented carbide [9][10][11][12].…”