ISSN:0947-5117    

DOI:10.1002/maco.19960471021

出版商:WILEY‐VCH Verlag GmbH    

年代:1996

数据来源: WILEY

ISSN:0947-5117    

DOI:10.1002/maco.19960471022

出版商:WILEY‐VCH Verlag GmbH    

年代:1996

数据来源: WILEY

ISSN:0947-5117    

DOI:10.1002/maco.19960471023

出版商:WILEY‐VCH Verlag GmbH    

年代:1996

数据来源: WILEY

ISSN:0947-5117    

DOI:10.1002/maco.19960471024

出版商:WILEY‐VCH Verlag GmbH    

年代:1996

数据来源: WILEY

摘要:

AbstractGrey cast iron (3.4%C–2.7%Si–0.4%Mn–0.5% P–0.008%S) with different morphology of graphite and different amount of ferrite, pearlite and eutectic phases has been subjected to corrosion and electrochemical tests in phosphoric acid solution, simulating the oxidized engine oil. The difference in the cathodic process and corrosion of studied materials has been mainly attributed to the variation of ferrite and pearlite volume fraction and to the presence of eutectic phases in the matrix of metals with different graphite shape. The possible assistance of the additions of Ce and Sn modificators on electrochemical behavior of cast iron has been discussed.Corrosion process accompanied by the hydrogen evolution leads to the formation of hydrogen induced cracks at the sharp edges of the graphite particles. In vermicular cast iron, hydrogen cracks form the spatial network causing the falling off some parts of metal and thus accelerating the degradation of this material under the corrosion‐erosion c

ISSN:0947-5117    

DOI:10.1002/maco.19960471002

出版商:WILEY‐VCH Verlag GmbH    

年代:1996

数据来源: WILEY

摘要:

AbstractThe effects of yttrium additions on the oxidation behaviour of Fe‐20Cr‐5Al(wt%) alloys have been investigated in oxidation tests and cyclic heating‐element tests at temperatures ranging from 1100 to 1400°C in air. Experimental results showed that the oxidation resistance of the alloys depends sensitively on the yttrium concentration. It was found that yttrium additions of about 0.045 wt% are sufficient to prevent the oxide scale from spalling. When the yttrium content is increased to more than 0.08 wt%, on the other hand, substantial internal oxidation of the alloys takes place, resulting in rapid wastage of the mat

ISSN:0947-5117    

DOI:10.1002/maco.19960471003

出版商:WILEY‐VCH Verlag GmbH    

年代:1996

数据来源: WILEY

摘要:

AbstractMicrobial influenced corrosion (MIC) occurred in copper drinking water installations of a water distribution area in Germany in a number of mainly institutional buildings. The extent of the manifestations of corrosion typical for this process differed considerably although the operating time of the affected installations was comparable. This difference must have been caused mainly by operating conditions and design parameters since the composition of the potable water and the quality of the copper tubes did not vary. This question has been investigated by setting up two test rigs operating at ambient temperature in an institutional building whose copper installation was severely affected by MIC. The corrosion process was successfully simulated in these test rigs.Corroded copper samples were taken from different house installations in this water distribution area and from the test rigs. The copper pipes of the different sources were inspected with respect to different operating conditions and design parameters. The obtained results cover the spectrum of the extent of the manifestations typical for this MIC process. Besides an induction period, a seasonal influence was evaluated for one institutional building.

ISSN:0947-5117    

DOI:10.1002/maco.19960471004

出版商:WILEY‐VCH Verlag GmbH    

年代:1996

数据来源: WILEY

摘要:

AbstractPitting of copper pipes was stimulated in the laboratory in synthetic tap waters with various water chemistries under stagnant conditions at room temperature. The primary interest was the effect of dissolved silica on uniform and localized attack. Long term experiments were conducted by immersion tests over eight months period. Short term tests were conducted using cyclic potentiodynamic tests. It is found that the effect of dissolved silica is similar to the behavior of an anodic inhibitor. The corrosion mechanism of copper in the presence of dissolved silica seems to proceed by a two step mechanism. An initial activation control corrosion reaction for a period of two months and a final diffusion control reaction with respect to dissolved silica. The effect of the ratio of dissolved silica to calcium ion concentration seems to indicate the predominate effect of dissolved silica. The effect of the ratio of dissolved silica to carbonate ion concentration seems to indicate the fact that increasing dissolved silica and/or decreasing bicarbonate ion concentration intensifies the corrosion rate. The effect of the ratio of dissolved silica to sulfate ion concentration seems to indicate the predominate effect of dissolved silica.

ISSN:0947-5117    

DOI:10.1002/maco.19960471005

出版商:WILEY‐VCH Verlag GmbH    

年代:1996

数据来源: WILEY

摘要:

AbstractThis paper concerns the investigation and comments of the causes of corrosion found to have taken place on stainless steel nitric acid plate coolers at a Caribbean site. The installation is briefly described, the occurrence and forms of corrosion are analysed and solutions discussed.

ISSN:0947-5117    

DOI:10.1002/maco.19960471006

出版商:WILEY‐VCH Verlag GmbH    

年代:1996

数据来源: WILEY

ISSN:0947-5117    

DOI:10.1002/maco.19960471007

出版商:WILEY‐VCH Verlag GmbH    

年代:1996

数据来源: WILEY