著者

筒井 光範

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.34, no.9, pp.526-527, 1985

著者

松本 桂一 篠原 孝順 笠松 昭宏

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.33, no.11, pp.643-648, 1984-11-15 (Released:2009-10-30)

参考文献数

13

被引用文献数

1 2

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As corrosion failures of 316L in urea synthesis solutions are due to either the active region dissolution or the corroison at the transition zone from the passive to the transpassive region, effects of process variables of the urea reactor on these two types of corrosion were electrochemically examined in order to advance the reliability of corrosion preventive methods. For making simple methods to evaluate resistance of 316L to the corrosion at the transition zone from the passive to the transpassive region, seven 316L specimens were immersed in an urea synthesis solution and the results were discussed by comparison with the results of Huey test and chemical compositions of the test specimens. The conclusions obtained are as followws.(1) 316L for the urea reactor required more amount of air to be injected for preventing active dissolution as the temperature of the reactor rose or the molar ratio of H2O/CO2 increased.(2) Sulfide, an impurity in CO2 gas, had a very detrimental effect on passivation of 316L. As it is not practical to compensate the harmfulness of sulfide by increase of the amount of air injection, the content of sulfide in CO2 gas should be lowered before feeding to the urea plant.(3) For reducing the corrosion at the transition zone from the passive to the transpassive region, higher molar ratio of NH3/CO2, lower ratio of H2O/CO2 and lower temperature were advantageous.(4) Sulfide was also harmful to this corrosion.(5) Annealed 316L was subject to weight loss owing to general corrosion and intergranular corrosion simultaneously at the transition zone from the passive to the transpassive region. Resistance of 316L to these two types of corrosion were correlated with Cr content in 316L and results of Huey test, respectively.

著者

太田 健一郎

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.33, no.5, pp.297-298, 1984-05-15 (Released:2009-10-30)

参考文献数

3

著者

能登谷 武紀

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.27, no.12, pp.661-670, 1978-12-15 (Released:2009-10-30)

参考文献数

130

被引用文献数

17 15

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This article is a review of recent literature on corrosion inhibitors for copper and copper alloys. Inhibitors are divided into two categories; (i) inorganic inhibitors, such as chromates, phosphates, and ferrous ions and (ii) organic inhibitors which include heterocyclic organic compounds, i. e., benzotriazole (BTA) and mercaptobenzothiazole (MBT) and their relative compounds. At present these are the most effective and widely used inhibitors in a variety of systems. The BTA derivatives such as tolyltriazole (TTA) and benzotriazole carboxylic acid will be the most promising inhibitors for copper and copper alloys. It is suggested that dimercaptothiadiazole (DMTDA) and triazinedithiol (TDT) and its derivatives may be used as a substitute of BTA. Effectiveness of both DMTDA and TDT is found to be better than BTA in some corrosive environments. Significant role of oxide films present on the metal surfaces is stressed in order to clarify the mechanism of protection performance of inhibitors. Long chain thio-compounds as film forming inhibitors are also described

著者

鶴田 孝雄

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.34, no.2, pp.135-139, 1985-02-15 (Released:2009-10-30)

参考文献数

28

被引用文献数

3 4

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Recent advances in the understanding of thermodynamic properties of aqueous electrolyte solutions at elevated temperatures, which is needed to calculate pH, are briefly reviewed, and examples of pH measurements at elevated temperatures are described.

著者

佐藤 教男

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.39, no.9, pp.495-511, 1990-09-15 (Released:2009-10-30)

参考文献数

55

被引用文献数

4 3

---

A review is given of some simplified concepts that will contribute to a better understanding of corrosion fundamentals. The corrosion process involves not only electrochemical reactions but also acid-base reactions, and it is the acid-base nature that diversifies the corrosion phenomena. Anions either catalyze or inhibit the anodic metal dissolution, and the passivation will result from the hydroxide-catalyzed mechanism of metal dissolution. Corrosion precipitates frequently control the selective mass transport in corrosion processes. Anion-selective precipitates accelerate and cation-selective precipitates decelerate corrosion propagation. A bipolar precipitate film, if anodically polarized, undergoes deprotonation and turns into a passive film. The electrochemical stability of passivated metals is determined by the electron energy band structure of the passive film. The passive film of n-type semiconducting oxides appears electrochemically more stable than the passive film of p-type semiconducting oxides.

著者

福谷 英二

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.27, no.3, pp.131-137, 1978-03-15 (Released:2009-10-30)

参考文献数

17

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A brief review of the technical literature shows that numerous investigations have been made on alternating stray current electrolytic corrosion of lead, iron, copper, alminum and other metals.Alternating current corrosion on lead, iron and copper seems to be caused mainey during the anodic half cycle, but alternating current corrosion on alminum may be caused during both anodic and cathodic cycles.Alternating current corrosion may be also caused by the rectification effects of corrosion product film and or polarization.Weight loss effect of alternating current on lead, iron and copper is less than 2 percents compared with the effect of equal direct current, but its effect on alminum is very high and more than 40 percents of equal direct current.The effective remedial measures of alternating current corrosion are selective drainage method and cathodic protection by galvanic anodes.

著者

鳥越 泰 市野 隆英 中野 昌信

出版者

社団法人 腐食防食協会

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.28, no.6, pp.343-347, 1979

被引用文献数

2

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In view of increasing trend of applying water cooling to electric machines, investigation has been made on corrosion of the copper pipe that is comprised in the internally water cooled power cable. Practical tests on corrosion of the copper pipe by flowing pure water were carried out using actual power cable under practical use conditions with regard to conductivity, temperature, and oxygen content of water, and flow velocity. The ranges of flow velocity were chosen to be much wider than could be encountered in the actual cooling system. Corrosion quantity of the copper pipe was determined from analyzed data on ion exchange resin and filter. The result of two times corrosion tests made about one year, in state where water temperature are below 80°C and flow velocity are below 3m/s, are as fellows. (1) Corrosion rate of the copper pipe reached 2μ/year, but the traces of pitting corrosion was not detected. (2) By electrolytic reduction, predominant component of black corrosion products on the copper pipe surface was identified with CuO. (3) Corrosion products were found to have considerable effect on stifling corrosion rate.

著者

出雲 茂人 末吉 秀一 北村 一弘 大園 義久

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.39, no.5, pp.247-253, 1990-05-15 (Released:2009-10-30)

参考文献数

6

被引用文献数

3 10

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In order to make clear the effect of volcanic environment on the corrosion of metals, corrosion tests where heating and cooling are repeated between 40°C and 20°C in SO2 gas atmosphere (150-200ppm) were carried out on the specimens, carbon steel (SS 41), copper, aluminium, and zinc-plated steel which were covered with volcanic ash on the surfaces. The corrosion phenomena were investigated by means of the measurement of mass loss for corrosion and electron probe microanalysis. For SS 41, aluminium, and zinc-plated steel, the corrosion is greatly accelerated by volcanic ash when it accumulate thick on the surface. The copper specimen corrodes faster in the case of no volcanic ash, while under the presence of volcanic ash the corrosion is greatly accelerated as volcanic ash layer becomes thicker. These effects of volcanic ash on the corrosion are attributed to capillary condensation and water-retaining effects of volcanic ash layer.

著者

竹本 幹男

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.35, no.2, pp.75-82, 1986-02-15 (Released:2009-10-30)

参考文献数

15

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Utilizing a combined loading Stress Corrosion Cracking (SCC) test apparatus, SCC threshold stress criteria of two material-environment systems where environmentally assisted passive films are formed has been studied. Two systems studied in this report are SCC of carbon steel in boiling nitrate solution (60%Ca(NO3)2+3%NH3NO4) and SCC of 70/30 brass in Mattsson's solution (ammonical solution) at room temperature.The test results obtained are summarized as follows:1) The threshold stress of nitrate SCC of carbon steel could be well explained by the maximum principal stress theory although the elastic fiailure of substrate metal was ruled by the shear strain energy theory. The environmentally assisted passive film of this system is supposed to be thich magnetite, and so brittle that it could suffer brittle fracture at lower stresses than the yield stress of substrate metal. Intergranular cracks might inititate at the fractured passive film along the grainboundaries oriented in perpendicular to the maximum principal tensile stress.2) SCC threshold stress of 70/30 bass in Mattsson's solution was in good agreement with the maximum principal stress theory. The SCC threshold stress is much lower than the elastic failure stress of substrate metal. The tarnished film of this system is supposed to have an elastic modulas higher than that of substrate metal. and fracture stress lower than the yield strength of film-free substrate metal.3) Based on the test results of previous and this reports, it was concluded, that the SCC threshold stress of the systems which developed an environmentally assisted film could be ruled by the maximum principal stress theory, and that the SCC threshold stress of metals which had a selfhealing ability of passive film in atmosphere could be ruled by the strain energy theory which is similar to the elastic failure stress criteria of substrate metal. Whether the threshold stress of APC-type SCC is evaluated by the strain energy theory or maximum principal stress theory seems to depend on the mechanical characteristics of passive film in a given system.

著者

三沢 俊平

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.32, no.11, pp.657-667, 1983-11-15 (Released:2009-10-30)

参考文献数

80

被引用文献数

13 26

著者

高橋 樟彦

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.23, no.11, pp.557-572, 1974-11-15 (Released:2009-10-30)

参考文献数

83

被引用文献数

1

著者

大石 不二夫

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.38, no.11, pp.599-607, 1989-11-15 (Released:2009-10-30)

参考文献数

10

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Survey of durability and its evaluation of polymeric materials are presented, by introducing the authors studies.Articles are shown as follows. 1) Differences between corrosion of metals and degradation of polymeric materials. 2) Concept on material system. 3) Development of testing apparatus for evaluating dynamic durability of plastics. 4) Factors affecting durability of polymeric materials. 5) Trials for simulation of durability. 6) Development of C-type method for estimating life against environmental stress cracking (crazing) of plastics.

著者

上田 龍二

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.38, no.4, pp.231-237, 1989-04-15 (Released:2009-10-30)

参考文献数

10

被引用文献数

2 6

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The photochemical machining of metals using a ferric chloride etchant is useful for producing micro machining parts and electronic parts such as printed circuit boards, shadow masks for CRT devices, IC lead frames etc. This paper presents the outlines of their examples of products, photo etching processes, photoresist materials for etch mask, machining accuracy, etchant composition, etching mechanism and characteristic phenomena.

著者

岡村 廸夫

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.34, no.7, pp.406-413, 1985-07-15 (Released:2009-10-30)

参考文献数

7

被引用文献数

1

---

Computers could be produced in quantities but interfaces are not. For any effective, productive, expandable, flexible and reliable computerized systems, standardized interface is a must. The IEEE-488 interface may look too complicated at first sight, it is understandable also for nonelectrician as its applications concern. Up to 15 interfaces or devices can be connected together into one bus system and it's speed is over 10 times faster than popular RS-232C. The 1-bus length is typically expandable to 20m, even more than 1km with special options.On the darker side, many capabilities of IEEE-488 could cause many mistakes on both usage and design. Larger systems may you build, if succeeded in getting more reliable devices and less noisier layout. For professionals and manufactures, it is strongly recommended to follow “A guidline for IEEE-488”** to get good compatibility, instead of inventing a new version to which nobody can talk.

著者

波戸崎 修 小山 昇

出版者

Japan Society of Corrosion Engineering

雑誌

防食技術 (ISSN:00109355)

巻号頁・発行日

vol.39, no.12, pp.709-716, 1990-12-15 (Released:2009-10-30)

参考文献数

35

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A review of the investigations on “Cold Fusion” is given. A brief history of developments of cold fusion researches is described. Representatives of excess heat generation, tritium production and neutron emmission in mainly electrolysis of D2O, i. e., Fleischmann-Pons experiments, are involved. Other experimental results suggesting the occurrence of a fusion reaction and the models proposed to account for the observations are also given.