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The following article concerns an apparatus constructed to study the basic principles of atmospheric corrosion both under laboratory conditions and for open‐air tests. Written by workers at the Institute of Physical Chemistry of the U.S.S.R. Academy of Sciences and the I. V. Stalin Steel Institute, it has been translated from the Russian by Aluminium Laboratories Ltd., of Banbury.

The inhibition of corrosion of Al‐Cu (4%) alloy B26S in decinormal solutions of phosphoric acid by different amines has been studied. The efficiency of the inhibitors increases in the order: triethylamine, di‐cyclohexylamine, diethylamine, cyclohexylamine, di‐n‐propylamine, isopropylamine, ethylenediamine, trimethylamine, n‐butylamine, dimethylamine, ethylamine, hexamine, n‐propylamine, methylamine. At constant acid concentration, the inhibitor efficiency increases with increase in the concentration of the inhibitor whereas at constant inhibitor concentration the efficiency decreases with increase in the concentration of the acid. Very little correlation appears to exist between either the pKb values or the molecular weight and the extent of inhibition. Maximum inhibition is achieved in those cases where the pH of the inhibited solution lies in the non‐corrosive range (4.5–8.5).

Proceedings of this conference, which was held last year, have now been published by the Academy of Science, U.S.S.R., Chemical Science Division, entitled: ‘The Fight Against Corrosion.’ Abstracts of the several papers given—mainly relating to stainless steels—are given below.

One of the main objects in Russian economy for some years has been the development of new sources of raw materials and the effective use and conservation of existing supplies. This aim is probably more intensive and important in regard to metals than anything else, and for this reason the fight against corrosion takes a leading place in research. The amount of work, indeed, directed to this end has reached enormous proportions, with a corresponding and impressive array of literature, in books, articles and proceedings.

The influence of some N‐containing organic compounds such as tetraethanol‐β‐octadecenyl succinylamide (TOSA), morphonil‐β‐hexenyl succinylamide (MHSA), ammonium naphthenyltri‐n‐butyl chloride (ANBC) and 1‐(2,4,6‐trimethylphenyl)‐3‐diethylaminopropanol‐2 (TMAP) as inhibitors for the corrosion of carbonized steel in mineral acid (HCl and H₂SO₄) solutions with different concentrations has been studied by using gravimetrical, electrochemical and polarization corrosion test methods. Observes that all compounds having surface active properties behave as inhibitors of a functional active cathodic type and have an inhibition effect at the first stage of corrosion in both acids, but more effectively in H₂SO₄. Shows that inhibition effect increases with increase of temperature in 0.5N H₂SO₄ solution and decreases with increase of temperature for the higher concentrations of acidic solutions. Shows that TOSA and TMAP compared with MHSA and ANBC enchance protection properties of adsorption layer.

The inhibition of corrosion of B26S aluminium by various colloidal substances in aqueous sodium hydroxide has been studied. The extent of corrosion decreased with increase in the concentration of the inhibition. At an inhibition concentration of 0.5% and above. The efficiency of the colloids in decimolar sodium hydroxide increased in the order: gelatin < dextrin < glue < agar agar < acacia < tragacanth (86%). The efficiency decreased with increase in the concentration of alkali, the P.I. at an inhibitor concentration of 1.5% in 1M sodium hydroxide being, glue (23%), gelatin (39%), dextrin (47%), agar agar (64%), acacia (71%) and tragacanth (86%). The inhibition appears to be due to the absorption of the inhibitor on the aluminium surface. An increase in temperature also decreased the extent of inhibition. The aver‐age energy of activation for corrosion of B26S aluminium in 0.1M sodium hydroxide appeared to be 12.5 KCal, the value in the presence of the inhibitor being somewhat higher.

To provide a summary of research work carried out mainly in the authors' group for evaluating various protective coatings including rustproofing oils, and also for studying corrosion inhibitors using the wire beam electrode (WBE) method.

A range of published papers published during the past 15 years was summarised and reviewed. Recent research work in the authors' group was also included, which involved the combined use of the WBE with electrochemical noise analysis and the scanning reference electrode technique.

The WBE method has been developed into a very useful tool of evaluating the performance of coatings and inhibitors. In particular, The WBE is uniquely applicable for determining the performance of coatings and inhibitors to control localised corrosion.

Focusing mainly on recent research.

A useful source of information for researchers and graduate students working in the areas of organic coating and inhibitor research.

The first summary or review on this research topic.

This paper aims to study the effect of small ruthenium additions through laser surface alloying of 304L stainless steel on the corrosion resistance when exposed to a 1 M sulphuric acid solution at 25°C.

In this study, the characteristics of laser-alloyed surface layers enriched with low concentrations of ruthenium, less than 0.3 Wt.%, were evaluated. Samples were manufactured by performing laser surface alloying on a 304L stainless steel and using a 304 stainless steel powder enriched with ruthenium. The welded surfaces were cross-sectioned and the microstructure and chemical composition were analysed; in addition, the depth of penetration was determined. The corrosion characteristics of these surface welds were investigated through electrochemical analysis such as open circuit potential measurements and potentiodynamic scans.

It was found that with the addition of ruthenium levels of more than 0.2 Wt.%, the corrosion characteristics when exposed to 1 M sulphuric acid improved in the enriched welded zone.

This study investigated the improvement of the surface layer of the 304L stainless steel because of the cost involved when ruthenium is alloyed in the bulk and showed that an improved corrosion resistance can be achieved in sulphuric acid at room temperature.

The hardness of the laser alloying was not significantly affected by the ruthenium, but more by the laser parameters.

This paper considers the improvement of 304L stainless steel through laser alloying with ruthenium.

Titanium research and development. The mechanical and physical properties of titanium alloys now in production or in an advanced stage of development are reviewed, with particular reference to their fatigue and notch‐fatigue characteristics. Creep characteristics at high temperatures, and the effect of heat‐treatment on this property are also discussed and a brief description is given of current investigations on hydrogen in titanium, properties of titanium tubing under pulsating pressure tests, and the production of extruded sections.—(N. P. Inglis, Metal Ind., London, 1957, 90, 185–188, 194, 205–206.)

High‐temperature aluminium alloys. This report is a compilation of corrosion studies performed during the period February 1955 to October 1957 to evaluate aluminium alloys developed for use as cladding material for fuel elements in pressurised water‐cooled reactors at temperatures ranging from 500 to 600°F. The alloy compositions included basic 2S aluminium containing nickel and iron, and special alloys of aluminium and copper. Specimens of each alloy were evaluated in semi‐static and in dynamic streams in isothermal test loops at the American Naval Laboratory. These loops were designed to simulate operating conditions of interest (exclusive of radiation) to the pressurised‐water reactor programme using water conditioning compatible with the most advanced technology for crude and corrosion control for pressurised water systems. Studies of the most promising alloys of aluminium and nickel were extended to include corrosion‐irradiation environments in the test loops at M.T.R. and boiling heat‐transfer conditions in heat throughput loops at A.N.L. The data include supplementary information published in reactor engineering division quarterly reports Nos. 1 and 2, internal memoranda, and reports to the U.S. Navy Task Group on Aluminium Alloys. Subsequent studies are to be described in another report. Referenced ANXL 5546, this 72‐page report has 47 illustrations and is priced $2.