Characterisation of the passive film on HIPed Stellite 6 alloy using X-ray photoelectron spectroscopy

In this paper results from the X-ray photoelectron spectroscopy (XPS) analysis of hot isostatically pressed (HIP) Stellite 6 in a 3.5% NaCl liquid medium are reported. The aim of the paper is to determine the composition of the passive film formed at different temperatures and link it to the corrosion properties. It has been shown that the alloy passivates spontaneously in air resulting in the formation of a thin oxide film comprising Cr and Co. Electrochemical oxidation at different temperatures results in the formation of a complex layer, the composition and thickness of which depends on the test temperature. Co was detected in the solution after corrosion; the Co amount increases as the test temperature increases and no Co is found in the passive film after corrosion.