1. |
Kinetics and mechanism of the reaction of iron with sulfur vapor in the temperature range of 250 to 500°C |
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Materials and Corrosion,
Volume 29,
Issue 6,
1978,
Page 385-393
Z. A. Foroulis,
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摘要:
AbstractThe kinetics and mechanism of the reaction between iron and sulfur vapor were investigated in the temperature range of 250 to 500°C and sulfur vapor pressures of 10 to 300 mm Hg. The sulfurization of iron has been found to follow a parabolic law. In the temperature range 250 to 370°C the reaction product consisted of an inner FeS scale, and an outer thin FeS2layer. The activation energy of this process amounts to 27 kcal/mole, and the parabolic reaction rate constant varies according to approximately the 1/2 power of the sulfur pressure. In the temperature range 370 to 500°C the reaction product consists entirely of an FeS scale. The activation energy of the limiting process in this temperature range is about 14 kcal/mole. The parabolic reaction rate constant at 500°C shows a sulfur pressure dependence according to approximately the 1/7 power of the sulfur vapor pressure. The mechanistic significance of the experimental results is considered in some det
ISSN:0947-5117
DOI:10.1002/maco.19780290602
出版商:WILEY‐VCH Verlag GmbH
年代:1978
数据来源: WILEY
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2. |
The high temperature oxidation behaviour of austenitic stainless steels |
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Materials and Corrosion,
Volume 29,
Issue 6,
1978,
Page 393-399
Royden Hales,
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摘要:
AbstractHigh temperature annealing in a dynamic vacuum has been utilised to induce the growth of duplex oxide over the whole surface of stainless steel specimens. It is found that duplex oxide grows at a rate which does not obey a simple power law. The oxidation kinetics and oxide morphology have also been studied for a series of ternary austenitic alloys which cover a range of composition between 5 and 20% chromium.A model has been developed from the observations to describe the formation of duplex oxide and the subsequent formation of a “healing layer” which virtually causes the oxidation process to stop. This phase tends to form at grain boundaries and a relationship has been derived for the reaction kinetics which relates the reaction rate with grain size of the substr
ISSN:0947-5117
DOI:10.1002/maco.19780290603
出版商:WILEY‐VCH Verlag GmbH
年代:1978
数据来源: WILEY
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3. |
The influence of sodium chloride on the atmospheric corrosion of steel |
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Materials and Corrosion,
Volume 29,
Issue 6,
1978,
Page 400-403
R. Ericsson,
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摘要:
AbstractThe influence of sodium chloride on the atmospheric corrosion of mild steel has been studied. Samples covered with sodium chloride crystals (8 m̈g NaCl · cm−2) have been exposed to an SO2‐free atmosphere at different relative humidities. The combined effect of sodium chloride crystals on a steel surface and sulphur dioxide in the atmosphere has been investigated at an SO2‐supply of 1 m̈g SO2· cm–2· h–1(1 ppm SO2). The corrosion attack was followed by periodic weighings. The corrosion products formed have been studied using the SEM‐technique. On exposure of samples with sodium chloride in an SO2‐free atmosphere the extent of corrosion increased with increasing relative humidity from 58% to 90%, interrupted by a sharp minimum at about 87% relative humidity. The SEM‐studies showed that tower shaped corrosion products were formed at a high relative humidity while filiform corrosion appeared when the relative humidity was lowered. At 90% relative humidity more corrosion was observed with clean steel samples and an SO2‐supply of 1 m̈g ·cm–2·h–1than with sodium chloride crystals on the surfaces (8 m̈g NaCl ·cm–2) in the absence of SO2. In the combined influence of sodium chloride on the steel surfaces and sulphur dioxide in the atmosphere a synergic effect was noticed at 90% relative humidity. At 70% relative humidity no influence of an SO2‐supply of 1 m̈g SO2·cm–2·h–1on the corrosion of steel samples with sodium chloride cr
ISSN:0947-5117
DOI:10.1002/maco.19780290604
出版商:WILEY‐VCH Verlag GmbH
年代:1978
数据来源: WILEY
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4. |
Korrosionsschutz in Rohren durch Betonauskleidungen |
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Materials and Corrosion,
Volume 29,
Issue 6,
1978,
Page 403-408
Gerhard Nagel,
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摘要:
AbstractGußeiserne Rohre verschiedener Durchmesser sowie Stahlrohre können durch Auskleidungen aus Zementmörtel wirkungsvoll gegen Korrosion geschützt werden. Dabei ergibt sich gleichzeitig eine Verbesserung der mechanischen Eigenschaften des Verbundes. Der Mörtel erreicht innerhalb von 28 Tagen Druckfestigkeiten von 700 bis 1000 kg/cm2, Biegezugfestigkeit über 100 kg/cm2und vermittelt auch bei Schäden am Metallrohr hohe Druckfestigkeit. Die Haftung zwischen Zement und Metall verbessert sich mit der Zeit: der frische Zement ist ziemlich porös, so daß Wasser bis zum Metall durchdringen kann; das Calciumhydroxid aus dem Zement und die Ferrihydrate auf der Metalloberfläche werden dann in den Beton eingebaut, so daß sich eine gute Verzahnung ergibt. Sulfatbeständige Spezialzemente halten in Abwasserleitungen Sulfatkonzentrationen bis 3000 mg/l und kurzfristig auch pH‐Wert
ISSN:0947-5117
DOI:10.1002/maco.19780290605
出版商:WILEY‐VCH Verlag GmbH
年代:1978
数据来源: WILEY
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5. |
Zur Korrosion von binären CuAl‐Legierungen in Schwefelsäure |
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Materials and Corrosion,
Volume 29,
Issue 6,
1978,
Page 409-414
R. Langer,
H. Kaiser,
H. Kaesche,
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摘要:
AbstractBei 25°C wurde in 1N Schwefelsäure die Korrosion binärer Al‐Legierungen mit Al‐Konzentrationen bis zu 16,5 Gew. % und unterschiedlicher Wärmebehandlung untersucht. Das Korrosionsverhalten der einzelnen Phasen wurde durch potentiokinetische Stromspannungskurven und durch potentiostatische Dauerpolarisationsversuche charakterisiert, die durch metallographische Untersuchungen an korrodierten Elektroden ergänzt wurden. Innerhalb eines begrenzten Potentialbereichs wurde die ausgezeichnete Korrosionsbeständigkeit der α‐Phase und das Auftreten von Entaluminierung in allen übrigen Phasen bestätigt. Die Ursachen für diese Unterschiede im Korrosionsverhalten we
ISSN:0947-5117
DOI:10.1002/maco.19780290606
出版商:WILEY‐VCH Verlag GmbH
年代:1978
数据来源: WILEY
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6. |
Aus Industrie und Technik |
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Materials and Corrosion,
Volume 29,
Issue 6,
1978,
Page 415-417
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ISSN:0947-5117
DOI:10.1002/maco.19780290607
出版商:WILEY‐VCH Verlag GmbH
年代:1978
数据来源: WILEY
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7. |
Umschau |
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Materials and Corrosion,
Volume 29,
Issue 6,
1978,
Page 417-419
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ISSN:0947-5117
DOI:10.1002/maco.19780290608
出版商:WILEY‐VCH Verlag GmbH
年代:1978
数据来源: WILEY
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8. |
Comprehensive papers covering several materials groups |
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Materials and Corrosion,
Volume 29,
Issue 6,
1978,
Page 420-423
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ISSN:0947-5117
DOI:10.1002/maco.19780290610
出版商:WILEY‐VCH Verlag GmbH
年代:1978
数据来源: WILEY
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9. |
Ferrous metals |
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Materials and Corrosion,
Volume 29,
Issue 6,
1978,
Page 423-432
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ISSN:0947-5117
DOI:10.1002/maco.19780290611
出版商:WILEY‐VCH Verlag GmbH
年代:1978
数据来源: WILEY
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10. |
Non‐ferrous metals |
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Materials and Corrosion,
Volume 29,
Issue 6,
1978,
Page 432-438
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ISSN:0947-5117
DOI:10.1002/maco.19780290612
出版商:WILEY‐VCH Verlag GmbH
年代:1978
数据来源: WILEY
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