Tungsten Carbide/Cobalt Wire - Material Information

Tungsten carbide/cobalt (WC–Co) composites are among the most successful ceramic-metal (cermet) materials, combining the exceptional hardness of tungsten carbide with the toughness and ductility of a cobalt matrix. Developed for demanding environments such as cutting tools, wear-resistant components, and electrodes for electrical discharge machining (EDM), these cermets offer superior wear resistance, thermal shock tolerance, and oxidation stability even under extreme operating conditions.

Material Overview

The WC–Co system typically consists of submicron tungsten carbide grains bound by 6–10 wt% cobalt. The high covalency of the WC lattice provides hardness values exceeding 1800 HV, while the cobalt binder ensures effective crack deflection and stress redistribution under load. Studies by Lin et al. (2017) revealed that grain refinement through AlN additions increases hardness to 17.1 GPa and improves transverse rupture strength to over 3100 MPa. At elevated temperatures, oxidation resistance is enhanced by the formation of stable WO₃ and CoWO₄ surface films that suppress oxygen diffusion (Luo et al., 2024). The inclusion of small alloying elements such as Ru or Cr further reduces oxide-layer spallation by stabilizing the Co matrix. WC–Co materials also demonstrate excellent thermal shock resistance, attributed to their high thermal conductivity (~85 W·m⁻¹·K⁻¹) and relatively low thermal expansion mismatch between the ceramic and metal phases.

Applications and Advantages

Tungsten carbide/cobalt wires are widely employed as EDM electrodes, cutting tool inserts, and wear-resistant parts in high-speed machining and forming operations. Their combination of toughness, oxidation resistance, and high compressive strength enables use in precision bearings, drilling tools, and die inserts subjected to extreme temperature cycling. Research by Ma et al. (2017) demonstrated that reducing cobalt content below 1 wt% can improve wear resistance by up to 20% through suppression of binder extrusion and WC grain pullout. WC–Co composites also maintain structural integrity at temperatures exceeding 800 °C, allowing application in environments where steel or conventional hardmetals fail. The alloy’s adaptability to sintering and additive manufacturing processes has further expanded its industrial utility across aerospace, energy, and defense technologies.

Goodfellow Availability

Goodfellow supplies high-purity tungsten carbide/cobalt wire for research and industrial applications requiring extreme hardness, wear resistance, and thermal stability. Custom compositions, diameters, and forms are available on request. Explore WC–Co and other advanced cermet materials through the Goodfellow product finder.

References

• Lin, N., He, Y., & Zou, J. (2017). Enhanced mechanical properties and oxidation resistance of tungsten carbide–cobalt cemented carbides with aluminum nitride additions. Ceramics International, 43(9), 7393–7400. https://doi.org/10.1016/j.ceramint.2017.01.145
• Luo, L., Wang, H., Lu, H., Liu, X., Liu, C., Fan, C., & Song, X. (2024). High-temperature oxidation-wear properties of Ru-doped cermet. Corrosion Science, 222, 111679. https://doi.org/10.1016/j.corsci.2023.111679
• Ma, R., Ju, S., Chen, H., & Shu, C. (2017). Effect of cobalt content on microstructures and wear resistance of tungsten carbide–cobalt-cemented carbides fabricated by spark plasma sintering. IOP Conference Series: Materials Science and Engineering, 207(1), 012019. https://doi.org/10.1088/1757-899X/207/1/012019
• Polyakov, E. V., Krasil’nikov, V. N., Tyutyunnik, A. P., Khlebnikov, N. A., & Shveikin, G. P. (2014). Precursor-based synthesis of nanosized tungsten carbide WC and WC–Co nanocomposites. Doklady Physical Chemistry, 457(1), 45–49. https://doi.org/10.1134/S0012501614070033
• Gordo, E., Sánchez, G., Biedma, Á., Villemur, J., Bertalan, C., Useldinger, R., de Nicolás, M., & Llanes, L. (2023). Oxidation and wear behavior of Co-free cemented carbides using Ti(C,N) and WC as ceramic phases. Powder Metallurgy and Metal Ceramics, 62(5–6), 269–279. https://doi.org/10.59499/ep235762742