Anodic behavior of 18-8 stainless steel under plastic deformation in H₂SO₄-NaCl solutions have been studied by means of constant strain rate, dynamic strain, and stress-relaxation method, static strain, in order to clarify the electrochemical conditions for stress corrosion cracking.
Anodic current density increases at the onset of the plastic deformation and with increasing strain. Anodic current density rises as the strain rate is lowerd.
Anodic current of 36% prestrained specimen increased with increasing time under the stress applied the elongation of 36%. Stress-relaxation test showed that anodic current density of prestrained specimen is higher than that of the solution treated specimen and increases with increasing prestrain. These behaviors are observed also on the specimen without the stress. Stress corrosion cracking and the surface striation due to localized dissolution are observed only in the prestrained specimen.
It is suggested that the localized dissolution accelerated by particular deformation structure such as stacking fault, deformation twin and strain induced martensite influence of the anodic current behavior.

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This study is concerned with the effect of chemical, electrochemical and mechanical surface preparation on initiation of strees corrosion cracking of austenitic and ferritic stainless steels in 300°C water containing 600ppm of chloride ion. Steels dealt with this report consist of commercial type 304, 316 and 430 stainless steels and laboratory melted 18 Cr-5 Ni and high purity 18 Cr-8 Ni steels. The results obtained can be summerized as follows: (1) The methods for preparing surfaces of specimens of annealed type 304, type 316, 18 Cr-5 Ni and high purity 18 Cr-8 Ni alloys and senditized type 304 steel exposed to high temperature water can produce a significant effect on susceptibility to stress corrosion cracking. Chemically or electrochemically polished specimens exhibit greater resistance to cracking than mechanically polished specimens. (2) Specimens of annealed and sensitized type 430 stainless steel, however, were not affected by the method for preparing surface. (3) Surface roughness of mechanically polished specimens appears not to be responsible for the shorter life to cracking of these specimens. (4) Oxide films grown in high temperature water on chemically or electrochemically polished specimens were dense and adherent in contrast with the porous and non-adherent oxide on mechanically polished specimens. Specimens with the former type oxide were less susceptible to cracking than specimens with the latter type oxide. (5) The protective nature of chemically or electrochemically polished specimens disappeared through cathodic treatment in 2 N-H₂SO₄ solution. (6) The effects of various surface preparations appear to opearate through the influence of their surface film formed during polishing. (7) Soft X-ray analysis of surface layer revealed the enrichment of nickel and chromium on the chemically or electrochemically polidhed specimens. This layer also, at least partly, contribute to inhibitive action to cracking of chemically or electrochemically polished surface.

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This article reviews X-ray photoelectron spectroscopy by which valuable information has recently been obtained for passive films on corrosion resistant alloys through analysis of surfaces. Included are the methods for calibration of binding energy of photoelectron and for obtaining integrated intensities of individual spectra after separation of superposed spectra from different valence-states of an element. By the use of integrated intensities, the thickness and composition of surface film and the composition of substrate alloy immediately under the surface film can be determined simultaneously. The convenient methods for qualitative and semi-quantitative analyses are also interpreted. Brief description is made for the works by many investigators in which X-ray photoelectron spectroscopy has been applied to analyze surface films formed on alloys in various environments.

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In order that alloys may be oxidation resistant, the following requirements should be satisfied,
(1) formation of uniform and compact oxide scale on the alloys,
(2) less cracking and spallation of this protective scale, and
(3) immediate healing of the scale, if cracking and spallation occurs.
In this paper is given a description on the details of these processes.

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The survey of the cost of corrosion to Japan has been made from April of 1976 to March of 1977 by the Committee on Corrosion and Protection (chairman: Prof. G. Okamoto), which was organized by Japan Society of Corrosion Engineering and Japan Association of Corrosion Control, with the Fund of Promotion of Machinery, supported by Ministry of International Trade and Industry. This survey revealed that the annual cost of corrosion to the nation amounts approximately to 2500 billion yen (9.2 billion U. S. dollars) on 1974 basis.

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