The corrosion behaviour of copper in simulated uterine fluid

Corrosion rate of copper in simulated uterine fluid was measured by polarization resistance technique and by weight loss method. Factors probably affecting the corrosion rate were considered. Copper specimens with different purities from 99.7 to 99.99% exhibited similar corrosion rates. The pH of the fluid played an important role. The corrosion rate at pH 6.3 was several times higher than that at pH 8.0. This could explain the great scatter of data for copper release rates presented in the literature, since significant variation in pH of human uterine fluid was reported. A maximum of corrosion rate was observed at a certain oxygen pressure. They were 0.12 atm for pH 7.0 and 0.06 atm for pH 8.0, respectively. Both cathodic reduction of surface film and chemical analysis of solution after corrosion testing proved that the proportion of soluble ionic copper in the whole corrosion products varied with pH values.