The Effect of Ni Content on the Corrosion Resistance of Some Fe–Cr–Ni Alloys in Simulated Body Fluids in the Presence of H2O2 and Albumin

Abstract

The stainless steel alloys are greatly utilized for human orthopaedic and implants. The electrochemical behaviour of the stainless steel of Fe–17Cr–xNi alloys (x = 8, 10, 14) has been studied in simulated body fluid containing H2O2 and albumin at 37 °C. The electrochemical behaviour of the Fe–17Cr–8Ni, Fe–17Cr–10Ni and Fe–17Cr–14Ni has been investigated using the potentiodynamic polarization and electrochemical impedance spectroscopy, EIS. The surface morphology of the three alloys was examined before and after immersion in the simulated body fluid containing H2O2 and albumin using scanning electron microscope. The elemental composition of the oxide layer formed on the surface of the alloys after immersion in the electrolyte was obtained using energy dispersive X-ray analysis, EDX, technique. The metals released into the electrolyte has been determined using atomic absorption spectrophotometry. The EIS and potentiodynamic polarization results demonstrate that the Fe–Cr–14Ni alloy attains highest polarization resistance and the smallest rate of corrosion than Fe–17Cr–8Ni and Fe–17Cr–10Ni alloys. Fe–17Cr–14Ni is slightly influenced by immersion in simulated body fluid containing H2O2 and albumin which is confirmed by SEM images and metal release via formation of protective passive film. The surface analysis has shown the participation of the different alloying elements in the passive film.