摘要:

AbstractThe corrosion of St 37, StE 36, Al 99,5 and Al‐Mg 3 in the chemical pairs of substances calcium chloride/ammonia, magnesium chloride/methylamine and magnesium chloride/methylamine/decane was investigated. The corrosion tests were performed in autoclaves at room temperature to 180 °C. The nominal duration of the experiments was 1000 hours.Rod shaped fatigue specimens with polished surfaces served as test specimens; these were fatigue tested after the corrosion treatments.All materials tested were compatible with calcium chloride/ammonia under the experimental conditions employed.Steel and aluminium showed similar behaviour against magnesium chloride/methylamine and magnesiumchloride/methylamine/decane, respectively.At room temperature and 70°C to 80°C the corrosion of steel and aluminium was low (wall losses in the order of 1 m̈m/a). Corrosion increased with increasing temperature. The activation energy for the reaction, which determined the rate of weight loss in magnesium chloride/methylamine/decane, was AEst= 0, 60 ± 0,18 eV for steel, and AEAl= 1, 07 ± 0,07 eV for aluminium.A corrosion treatment on aluminum fatigue specimens after 1000‐1500 hours at 110 °C caused a notable decrease in fatigue strength; no such behaviour was noted for steel, even when corroded

ISSN:0947-5117    

DOI:10.1002/maco.19790300702

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractThis paper summarizes the results of an investigation of the corrosion and electrochemical behavior, including cathodic hydrogen absorption, of titanium in acidic and alkaline sulfidic solutions. The effect of chloride and cyanide ions on the corrosion behaviour of titanium in sulfidic solutions was also studied. Titanium in acidic and alkaline sulfidic solutions exhibits a stable passive corrosion potential and negligible corrosion. Chloride and cyanide ions do not affect the corrosion behavior of titanium in sulfidic solutions. Cyanide ions under conditions of cathodic polarization tend to promote activation of titanium. Cathodic polarization at temperatures higher than 72 °C promotes hydrogen uptake in titanium and formation of titanium hydride. The rate of hydrogen uptake increases with decreasing pH and increasing temperature. Cyanide ions tend to promote the rate of hydrogen uptake, whereas chloride ions have essentially no effect

ISSN:0947-5117    

DOI:10.1002/maco.19790300703

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractEs wurden pH‐Werte und Metallionenkonzentrationen bei der anodischen Auflösung von Reineisen, Fe 1 Cr, Fe 5 Cr, Fe 18 Cr 9 Ni in 3 TMKCl in einem Modellspalt unter sauerstofffreien Bedingungen ermittelt. Im Falle von Reineisen wurden keine tieferen pH‐Werte als 4,65 gefunden. Bei chromhaltigen Stählen ergab sich mit steigendem Chromionengehalt des Spaltelektrolyten ein Abfall des pH‐Wertes bis auf rund 0. Dieser kann nicht mit der einfachen Hydrolyse dreiwertiger Chromionen erklär

ISSN:0947-5117    

DOI:10.1002/maco.19790300704

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractThe apparent tensile fracture strains, at which cracking of α‐Al2O3scales formed on Fe‐Cr‐Al‐Y alloys during oxidation in 1 atm oxygen at 1200 °C occur, have been determined by two methods at room temperature. The values are reproducible and depend on the oxidation time but are within the range 1.4% to 2.3%. These are significantly higher than other published values for thermally formed oxides. It has also been observed that an intermediate thermal cycle to room temperature during the oxidation period does not affect significantly the subsequently measured fracture strain. These relatively high values are discussed in terms of two tentative hypotheses, one relating to flaws in the oxide, the other to possible loss of cohesion of oxide which is too fine to be detected by the met

ISSN:0947-5117    

DOI:10.1002/maco.19790300705

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

摘要:

AbstractA system using a vibratory probe oscillating in close proximity to a specimen surface was improved in order to study the effects of tensile stress on the initial stages of cavitation damage: the temperature distribution on the stationary specimen came within ± 0.3 °C, and the errors in the experimental results were able to be kept below ± 3%.A tensile stress applied on such ductile metallic materials as aluminum, iron (ferrite) and mild steel inhibits cavitation damage in the early stage: the incubation period was extended to a maximum of five times. However, the damage is accelerated in the stage affected with weight loss. An applied tensile stress on such brittle material as cast iron accelerates damage both in the incubation period and the following periods of damage.The mechanism of these favorable and unfavorable effects of tensile stress on cavitation damage has been discuss

ISSN:0947-5117    

DOI:10.1002/maco.19790300706

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

ISSN:0947-5117    

DOI:10.1002/maco.19790300707

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

ISSN:0947-5117    

DOI:10.1002/maco.19790300708

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

ISSN:0947-5117    

DOI:10.1002/maco.19790300709

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

ISSN:0947-5117    

DOI:10.1002/maco.19790300710

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY

ISSN:0947-5117    

DOI:10.1002/maco.19790300712

出版商:WILEY‐VCH Verlag GmbH    

年代:1979

数据来源: WILEY