The effect of increasing vanadium carbide (VC) content on the corrosion behaviour of tungsten carbide – 10 wt% cobalt hard metals was investigated in 1 M hydrochloric (HCl), and sulphuric (H2SO4) acids solutions. Increasing VC content makes the open circuit potential (OCP) in the test solutions more negative than the base alloy. Specimens exhibited pseudo passivation in all the test solutions. Increasing VC led to decreasing corrosion current density. However, the corrosion current densities during chronoamperometric tests were lower for 0 wt% VC. XRD and Raman spectroscopy showed that hydrated WO3 formed in the surface films of all specimens in hydrochloric acid (HCl), while hydrated vanadyl sulphate also formed for higher VC content specimens in sulphuric acid (H2SO4).
Reference:
Konadu, DS, Van der Merwe, J, Potgieter, JH et al. Corrosion behaviour of WC-VC-Co hardmetals in acidic media. Corrosion Science, Vol. 52(9), pp 3118–3125
Konadu, D., Van der Merwe, J., Potgieter, J., Potgieter-Vermaak, S., & Machio, C. N. (2010). Corrosion behaviour of WC-VC-Co hardmetals in acidic media. http://hdl.handle.net/10204/4996
Konadu, DS, J Van der Merwe, JH Potgieter, S Potgieter-Vermaak, and Christopher N Machio "Corrosion behaviour of WC-VC-Co hardmetals in acidic media." (2010) http://hdl.handle.net/10204/4996
Konadu D, Van der Merwe J, Potgieter J, Potgieter-Vermaak S, Machio CN. Corrosion behaviour of WC-VC-Co hardmetals in acidic media. 2010; http://hdl.handle.net/10204/4996.
Copyright: 2010 Elsveir. This is the post print version of the work. The definitive version is published in Corrosion Science, Vol. 52(9), pp 3118–3125