Corrosion properties of novel γ′-strengthened Co-base superalloys

► Electrochemical behaviour of novel Co-base superalloys and pure Co in NaCl solution. ► Materials show comparable limited passivation followed by severe pitting corrosion. ► Oxidation of the alloys leads to the formation of highly protective oxide scales. ► Increased oxidation time and temperature improve protective properties of the layers. ► Si-addition further increases the corrosion resistance of oxidised alloys in NaCl.