ELECTROCHEMICAL BEHAVIOUR OF Al-BRASS IN SEAWATER
Corrosion of the Al-brass in 3.5 % NaCl solution and natural seawater was investigated with potentiodynamic polarization technique. Corrosion rate obtained in natural seawater was higher than in 3.56 % NaCl solution. The metallographic examinations indicated the occurrence of pitting corrosion in both cases.
Characteristics of the Al-Brasses Affected Corrosion Properties
The Al-brasses are considered corrosion resistant construction materials often used to pipe systems in energy industry, where they are exposed to flowing liquids environments. In that system the brasses are loaded chemically and mechanically. The aim of our research work is to compare corrosion properties of four Al-brasses produced by different manufactures because in operation conditions they have dissimilar reliability and durability. The examined Al-brasses have similar chemical composition but differ in microstructure, surface state what affects their corrosion and mechanical properties. The effect of the mentioned parameters on corrosion and mechanical susceptibility to degradation are investigated by chosen experimental methods.
ESCA investigation of iron-rich protective films on aluminium brass condenser tubes
Abstract The object of this investigation was to examine the nature of the protective oxide layers on an aluminium brass condenser tube which had been in service at Fawley under an operating regime in which the cooling water was regularly dosed with ferrous sulphate for protection against pitting corrosion. The protective films have been analysed by means of XPS (ESCA) and found to contain mainly Cu + and Fe 3+ ions. Of more interest were extensive areas in which the iron deposits are non-adherent and non-protective. XPS analyses show that these deposits are separated from the underlying brass by a layer rich in zinc and magnesium but containing no iron. Some indications are given of how this intervening layer could have formed.