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This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/eb006785. When citing the article, please cite: M.N. Desai, S.S. Rana, M.H. Gandhi, (1970), “Corrosion inhibitors for copper”, Anti-Corrosion Methods and Materials, Vol. 17 Iss: 6, pp. 17 - 21.

The discovery of the Hall‐Herqult process for the manufacture of aluminium made it possible to obtain the metal in large quantities. Soon it attained the position of a major industrial metal due to its lightness combined with strength, capacity to take up a high polish, excellent conductivity of heat and electricity. Moreover it gives a wide range of extremely valuable alloys with diverse elements such as copper, magnesium, nickel, silicon, zinc, etc.

This concluding part reviews the actions of inhibitors to acidic, ammonical, organic, atmospheric and miscellaneous product corrosion on aluminium. The comprehensive reference list is also concluded.

Due to the constituent nitrogen atom of the amino group, amines have been extensively used as inhibitors of metallic corrosion. This article reviews the reported uses of aniline and related aromatic amines as corrosion inhibitors.

Organic compounds containing sulphur, nitrogen and oxygen atoms are capable of retarding metallic corrosion. As the thiourea molecule contains one sulphur and two nitrogen atoms, thiourea and its derivatives are potential corrosion inhibitors. While extensive investigations have been carried out on inhibitor properties of thiourea, due attention has not yet been paid to a systematic study of inhibitor action of thiourea derivatives. However, several substituted thioureas have been investigated as corrosion inhibitors. The applications of thiourea and its derivatives as corrosion inhibitors reported in literature up to 1967 are narrated in this article.

COPPER is by far the most important non‐ferrous metal used in industry. By virtue of its valuable physical and mechanical properties, long life, comparative cheapness and high scrap value, it occupies a position next only to iron and steel in commercial importance.

Zinc is one of the most important nonferrous metals and finds extensive use in metallic coatings. It is resistant to atmospheric attack and corrodes rapidly only in highly polluted air. It is resistant to most fresh waters but its resistance to sea water and to very soft water is lower. In many aerated hot waters, reversal of polarity between zinc and iron occurs at temperatures of 60°C or above. The corrosion products of zinc are readily soluble both in alkalis and acids and protect the metal surface only in neutral media. In neutral solutions, zinc is corroded mainly by oxygen depolarisation. The dissolution rate of zinc in acids is greatly affected by the over‐potential of hydrogen evolution at cathodic inclusions.

2: Aminobenzoic acids as inhibitors in nitric acid Ortho, meta and para aminobenzoic acids have been studied as corrosion inhibitors for 60/40 brass in nitric acid. Ortho and para aminobenzoic acids are cathodic in action whereas meta aminobenzoic acid acts by influencing both the cathodic and anodic reactions.

Introduction Aldehydes, ketones, amines, anilines and organic sulphur compounds are being studied in this laboratory as corrosion inhibitors for aluminium alloys. The present paper deals with salicylaldehyde, p‐hydroxybenzaldehyde, cinnamicaldehyde and anisaldehyde as corrosion inhibitors for aluminium‐57S in hydrochloric acid solutions. It is known that the behaviour of inhibitors changes with the metal or even with the change in the composition of the alloy.

Diethylene triamine, triethylene tetramine and tetraethylene pentamine have been studied as cathodic corrosion inhibitors for aluminium‐57S in hydrochloric acid. Compared to diethylene triamine and triethylene tetramine, tetraethylene pentamine is less satisfactory. Diethylene triamine and triethylene tetramine protect aluminium 57S in 1·ON HCl in the temperature range 35°C–55°C. The effect of external cathodic and anodic currents is studied.