Corrosion handbook for stainless steels

Corrosion handbook for stainless steels

Corrosion Science, Vol. 36, No. 11, pp. 1949-195(I, 1994 Pergamon Elsevier Science Ltd Printed in Great Britain. BOOK REVIEWS Corrosion Handbook fo...

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Corrosion Science, Vol. 36, No. 11, pp. 1949-195(I, 1994

Pergamon

Elsevier Science Ltd Printed in Great Britain.

BOOK REVIEWS Corrosion Handbook for Stainless Steels. ISBN 91-630 2122-6. Avesta Sheffield AB 1994, 132 pp. Hardback: £20; Paperback: £15. The Preface of this book states that it is a replacement for an earlier edition produced by the Scandinavian manufacturers in 1979 which has been out of print for some years. The first 64 pages contain a series of papers describing and explaining the resistance of stainless steels to attack in atmospheric, wet and high temperature environments, as well as their use for various purposes where their properties offer special advantages. The subsequent 88 pages contain a large number of Tables and Figures describing the resistance of various materials to different environments by concentration and temperature. The series of short papers present a condensed expert exposition of the corrosion properties of stainless steels. They pay attention to the various standard tests that are used in evaluating stainless steels and give results on various grades. Some of these are ASTM tests, others derive from the Materials Technology Institute of the Chemical Process Industries (MTI). Tests are discussed in relation to potential users of stainless steels. The paper on seawater is a good example. The Pitting Resistance Equivalent (PRE) is given: P R E = % C r + 3.3%Mo + 30%N but the point is made immediately that the effects of various production processes and welding may overshadow a formula derived from accelerated laboratory tests performed on perfectly heat treated base material. The effects of the biofilm are emphasized, a thin microbial slime layer which forms quickly on an inert surface. It ennobles the corrosion potential, making a steel more prone to pitting attack. It has a strong catalytic effect on the cathodic process, increasing the current density by up to two orders of magnitude, but does not appear to affect the anodic process. The activity of the biofilm ceases at a certain temperature which may vary from one seawater to another. In the Mediterranean close to G e n o a this temperature is 40°C. Some results are given comparing crevice corrosion at 25 and 70°C over 3 and 6 months, respectively. The observed attack was much deeper after testing at the lower temperature in spite of the shorter exposure time. The effects of chlorination used to remove biological activity are then described. It raises the corrosion potential but lowers the cathodic current density. The conclusion is that the risk of crevice corrosion is increased by chlorination but that the propagation rate is reduced. This effect is shown in some results. The corrosivity of chlorinated seawater increases with increasing temperature. Since resistance to crevice corrosion increases if steels are exposed to a less corrosive environment some time before contact with an aggressive environment, it is suggested that chlorination should be brought up to the intended level slowly initially or started in an intermittent fashion. There are very informative papers, inter alia, on Welding, Steels in the Pulp and Paper Industry, Oil and Gas Production, Flue Gas Desulfurization Scrubbers. The Corrosion Tables include quite a few isocorrosion graphs. At least 300 chemicals are covered, including acids, some contaminated with common impurities. Sulphuric acid, for example, is included with 18 different chemicals. Other less 1949

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Book reviews

expected chemicals include molten Sb, Bi, Zn and Borax, as well as commercial mixtures, for example, fixing solution. The information is shown as the corrosion rate for each of 13 stainless steels, together with carbon steel and titanium. Risks of pitting and crevice corrosion and stress corrosion cracking are indicated. This is an excellent publication. I am certain that it will prove invaluable for designers and selectors of steels at whom it is aimed. In addition it should be required reading for teachers and students of corrosion alike. It provides a lot of information in concise form. J O H N SCULLY Concise Encyclopedia of Chemistry. Walter de Gruyter & Co., Berlin. Translated and revised by M. V. Eagleson, 1994. ISBN 3-11-011451-8, $69.95. Scientific encyclopedia, like dictionaries and catalogues, are often enjoyed by browsing through them, after first consulting them for some specific information, and I have similarly also enjoyed Concise of Encyclopedia Chemistry. With some 12,000 entries taken from general, inorganic, organic, physical and technical chemistry, plus around 1600 figures and 300 tables, only a personal survey of my interests is possible. I found all the major topics and their main points present, and sometimes some information of which I was not aware. This book will be helpful to both chemists and chemical technologists and should be on library shelves, and in the Safety Supervisor's office as it provides a useful but different slant on the information in Safety Handbooks. I looked up topics on which I lecture and found good concise descriptions and definitions, and ideas for handouts. This book will thus aid lecturers in making concise notes and will be useful to students for expanding the notes they have taken, and for revision. Students generally consult their textbooks for explanations, which can be too detailed and a concise account examined first is often a better way to acquire understanding. However, since students are unlikely to consult scientific encyclopedias as a matter of course, lecturers need to make their students aware of this book, and should stress the necessity for reading first the page 'How to use this book': without understanding the shorthand used the book's value will not be fully appreciated. I also found that words or phrases that I looked up, if not immediately explained, directed me to alternative or modern names (there is an excellent Nomenclature section), or to the parent topic, e.g. Freezing curve: see Melting diagram. There are also boxes which contain useful summaries on poisonous materials, including their mode of action and initial treatment, and these should remind and alert old and young chemists to take necessary precautions. This book is a translation from the German edition of 1993 into American English (color and aluminum) and has been well proof-read. I was able to detect one minor error: both polonium and francium were reported as discovered, in 1898 and 1939, respectively, by M. Curie and were noted as 'named in honor of her native land'. Marie Curie died in 1 9 3 4 . . . the French woman Margueritte Perey discovered francium. This book is what it claims to be, a concise encyclopedia of chemistry, and will be valid for many years. The publishers, editors and translator are to be congratulated, and provided your library and lecturing staff make its addition to your library well advertised to students then its value will be appreciated and its pages turned over often. Your next step is to see your l i b r a r i a n . . . (but get yourself a copy if you can). T. R. GRIFFITHS