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Certain classes of organic chemicals that can behave like carbon black in protecting polythene from thermal degredation have recently been developed at Bell Telephone laboratories in the U.S.A. Mrs. A. Worthington and Dr. W. L. Hawkins described their discovery at a recent meeting of the American Chemical Society in New York. They demonstrated that a number of compounds containing alternating unsaturated bonds provide excellent thermal anti‐oxidant properties in combination with previously reported sulphur‐bearing compounds.

In the previous two articles the emphasis was on wet and electrochemical techniques, with particular reference to the potentiostat. The physical examination of corrosion products is of equal importance, especially, for example, in the study of oxidation by dry gases at elevated temperatures where electrochemical studies are not normally feasible. In this article the application of physical techniques to corrosion studies will be discussed.

The Central Electricity Research Laboratories (CERL) at Leatherhead is the largest and longest established of the research centres of the Central Electricity Generating Board. Its staff numbers about seven hundred, three hundred of whom are professional scientists, and their programmes cover research into generation of electricity by coal‐ and oil‐fired power stations, and into transmission and distribution. CERL's activities include those as diverse as magneto‐hydrodynamics and the microbiology of soils; the dispersion of plumes from high chimneys and the basic physics of brittle fracture in metals. Three quarters of its work and almost all the corrosion research relates to generating electricity, although it has some of the best facilities in the world for studying the transmission of electricity at very high voltages, and the first corrosion problem it tackled was on steel cored aluminium conductors.

Introduction A STUDY of the detailed morphology of corrosion films formed on metal often leads to an interpretation of the observed rate of corrosion based on a physical model of the diffusion processes by which the oxide grows. This is particularly valuable, for example, in deciding whether an abrupt change in rate of corrosion of a metal or an alloy corresponds to cracking of the oxide film or, perhaps, to formation of a new oxide phase.

The above Congress, being held at the Imperial College of Science and Technology, London, from April 10–15, has been described as likely to be the corrosion event of the decade. Size alone is no criterion, though over 80 papers are being presented, but the standing of many of the corrosionists associated with the Congress is, perhaps, the best indication of the truth of this statement. Summaries and abstracts of some of the papers appear in the following pages. More will be published in next month's issue.

New Research Laboratory. The recently opened Passfield Research Laboratories at Passfield, Hants., will be devoted to combined research programmes for Metal Containers Ltd., the U.K. company, and Inland Steel Container Co., the U.S. company, and the work being undertaken is expected to lead to improved containers in steel, plastics and fibre materials and new steel/plastic and fibre/plastic packaging systems.

BUILDING WITH ALUMINIUM. For over 60 years satisfactory service has been achieved in the building industry with aluminium components. Success has been apparent when the correct alloy has been correctly applied. However, examples of corrosion failure generally attract more attention than the smooth success stories. Such an example is embodied in a circular sent out last month by the Ministry of Housing and Local Government to local authorities concerning corrosion in certain types of aluminium bungalows. The circular follows an investigation by the Ministry and the Building Research Station.

Cathodic protection by galvanic or impressed current techniques is probably the most favoured method of obviating the corrosion of buried and immersed metals. The theoretical principles and the economics involved in such protection are well established now and have been the subject of numerous papers, monographs and reviews. Cathodic protection is, however, still far from being an infallible method of corrosion prevention primarily because (a) the cathodic protection conditions necessarily change with the environment, (b) complete corrosion protection is rarely achieved in practice (see below), and (c) corrosion of an apparently protected structure may occur through the presence of stray currents

Three unusual forms of ‘tell‐tale’ inlet impingement attack (slot, star and crescent) are described, together with examples of other similar interesting forms of attack. The paper is based on direct observations made in the field and on examination of samples returned to the laboratory. These investigations have revealed several factors, not previously reported, which can affect corrosion in heat exchangers. This paper, not previously published, has been revised since the author presented it to the first International Congress on Metallic Corrosion.

The purpose of this paper is to optimize a suitable electrochemical method in evaluating the corrosion rate of structural materials of 20# carbon steel, P280GH carbon steel, 17-4PH stainless steel, 304 stainless steel and Alloy 690TT in high-temperature and high-pressure (HTHP) water of pressurized water reactor secondary circuit system.

Weight-loss method has been used to obtain the corrosion rate value of each structural material in simulated HTHP water. Besides, linear polarization method and weak polarization curve-based three-point method and four-point method have been compared in obtaining a sound corrosion rate value from the potentiodynamic polarization curve. Scanning electron microscopy (SEM) and atomic force microscope have been used to characterize the microstructure and corrosion morphology of each structural material.

Although there is deviation in gaining the corrosion rate value compared to weight-loss test, the weak polarization curve-based four-point method has been found to be a suitable electrochemical method in gaining corrosion rate value of structural materials in HTHP waters.

This paper proposes a suitable and reliable electrochemical method in gaining the corrosion rate value of structural materials in HTHP waters. The proposed weak polarization curve-based four-point method provides a timesaving and high-efficient way in corrosion rate evaluation of secondary circuit structural materials and thus has a potential application in nuclear power plants.