J. González-Rodríguez, M. Casales, M. Amaya, L. Martínez
{"title":"Effect of heat treatment on corrosion behaviour of deposited Fe–40Al intermetallics","authors":"J. González-Rodríguez, M. Casales, M. Amaya, L. Martínez","doi":"10.1179/000705901101501514","DOIUrl":"https://doi.org/10.1179/000705901101501514","url":null,"abstract":"Abstract A study using electrochemical techniques of the susceptibility to corrosion in 0·1M NaCl solution (pH 3) of atomised and deposited Fe–40Al (at.-%) intermetallic material at room temperature is reported. Specimens were heat treated at temperatures of 600 and 900°C for 24 and 72 h. Potentiodynamic polarisation, linear polarisation resistance, potential–time, and electrochemical current noise data were collected. The untreated material displayed higher corrosion resistance than the heat treated material. In the treated material, the corrosion resistance increased with both the time and temperature of heat treatment. Also, untreated material was more susceptible to pitting corrosion than heat treated material. As the temperature or the time of heat treatment was increased, the material became more resistant to pitting. This improvement in resistance to pitting was related to a decrease in surface defects, such as pores and cracks, and an increase in grain size. Thus, heat treatment lowered the number of active sites and helped the material to establish a more protective film.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"9 1","pages":"65 - 69"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89169844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Corrosion failure of sensor wire in leak detection system of thermally insulated underground pipeline","authors":"J-G. Kim, Youngjoo Choi","doi":"10.1179/000705901101501442","DOIUrl":"https://doi.org/10.1179/000705901101501442","url":null,"abstract":"Abstract The leak detection system of a thermally insulated pipeline has frequently malfunctioned due to sensor wire failures. The failures are attributed to the applied sensing current when the insulation becomes wet. Pits were generated by the sensing current and acted as stress concentration sites.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"13 1","pages":"29 - 32"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74345130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Quartarone, A. Zingales, T. Bellomi, D. Bortolato, G. Capobianco
{"title":"Study of inhibition mechanism and efficiency of indole-5-carboxylic acid on corrosion of copper in aerated 0·5M H2 SO4","authors":"G. Quartarone, A. Zingales, T. Bellomi, D. Bortolato, G. Capobianco","doi":"10.1179/000705900101501399","DOIUrl":"https://doi.org/10.1179/000705900101501399","url":null,"abstract":"Abstract Inhibition of the corrosion of copper in aerated 0·5M sulphuric acid solutions containing various concentrations of indole-5-carboxylic acid was studied in the temperature range 25–55°C using potentiodynamic curves (Tafel lines), weight loss, analytical methods, and determination of double layer capacitance. The corrosion rates reveal good corrosion inhibition, up to 95% in the concentration range of 1 × 10-4–4 × 10-3M. Tafel anodic slopes in inhibited acid solutions are considerably higher than those in uninhibited acid solutions. This points to a change in the corrosion mechanism of copper in the presence of indole-5-carboxylic acid. Under these conditions, copper could electro-oxidise primarily to Cu+ rather than to Cu2+, forming slightly soluble [Cu–(indole-5-carboxylic)n ]+(ads) complexes. Corrosion rates determined by the weight loss method in both the absence and presence of inhibitor are much higher (on average by a factor of about 6) than those obtained with the potentiodynamic method. This points to a limitation of the Tafel line extrapolation method in corrosion rate determination. The double layer capacitance–potential curves indicate considerable adsorption of the inhibitor over a wide potential range (-600 to +200 mV with regard to Ecorr ).","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"2004 1","pages":"304 - 310"},"PeriodicalIF":0.0,"publicationDate":"2000-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83031273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Atmospheric corrosion of zinc Part 2: Marine atmospheres","authors":"E. Almeida, M. Morcillo, B. Rosales","doi":"10.1179/000705900101501362","DOIUrl":"https://doi.org/10.1179/000705900101501362","url":null,"abstract":"Abstract This paper summarises the results obtained in the MICAT (Mapa Ibero-Americano de Corrosão Atmosférica (Latin American Map of Atmospheric Corrosion)) atmospheric corrosion project (an Iberoamerican project on atmospheric corrosion, involving 14 countries and 75 atmospheric test sites) for zinc specimens exposed in the Latin American region for 1–4 years at 23 pure marine and 19 mixed marine (i.e. SO2 polluted) sites. The atmospheres at these sites were characterised climatologically and in terms of their pollution levels so that their corrosivity could be expressed in accordance with ISO standards. Morphological and chemical characterisation of the zinc corrosion product layers (ZCPLs) was performed using scanning electron microscopy coupled with energy dispersive spectrometry (SEM–EDS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and soluble salt evaluation techniques. The results obtained show that the corrosion rate of zinc is a function of both the chloride pollution level and the time of wetness. Some synergetic effects of Cl- and SO2 were demonstrated, although some special types of behaviour were also observed.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"17 1","pages":"289 - 296"},"PeriodicalIF":0.0,"publicationDate":"2000-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85727219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Atmospheric corrosion of zinc Part 1: Rural and urban atmospheres","authors":"E. Almeida, M. Morcillo, B. Rosales","doi":"10.1179/000705900101501353","DOIUrl":"https://doi.org/10.1179/000705900101501353","url":null,"abstract":"Abstract This paper summarises the results obtianed in the MICAT (Mapa Ibero-Americano de Corrosão Atmosférica (Latin American Map of Atmospheric Corrosion)) atmospheric corrosion project (an Iberoamerican project on atmospheric corrosion, involving 14 countries and 75 atmospheric test sites) for zinc specimens exposed for 1–4 years in 21 rural and urban atmospheres of the Latin American region. During the study, all of these atmospheres were characterised according to international standards. Complementary morphological and chemical studies were carried out using scanning electron microscopy coupled with energy dispersive spectrometry (SEM–EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) techniques, in order to correlate atmospheric characteristics and the properties of zinc corrosion product layers (ZCPLs). Soluble salts retained in these ZCPLs were also determined. The study has provided clear evidence about the wide range of zinc corrosion rates occurring in rural atmospheres and suggests an interpretation of this behaviour.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"231 1","pages":"284 - 288"},"PeriodicalIF":0.0,"publicationDate":"2000-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79207415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ship impressed current cathodic protection – modulations of system current outputs by propeller/shaft rotation on physical scale model hull","authors":"D. Tighe-ford, J. Dahele","doi":"10.1179/000705900101501317","DOIUrl":"https://doi.org/10.1179/000705900101501317","url":null,"abstract":"Abstract Physical scale modelling was employed to examine the effect of propeller/shaft rotation on the current outputs of ship impressed current cathodic protection (ICCP). When a one-hundredth scale metal hull was protected in diluted sea water, propeller rotation produced low frequency modulations of output. Two propellers rotating resulted in two sinusoidal frequencies, the higher frequency ‘carrier’ being amplitude modulated by a lower frequency envelope. There was only the ‘carrier’ waveform present when only one propeller was rotated. The ‘carrier’ frequency (4·67–0·83 Hz) was related to the speed of shaft rotation and was apparently determined by the faster propeller. Envelope frequencies (0·48 and 0·42 Hz) corresponded to differences in speed of the two propellers. Possible causes of this corrosion control phenomenon are proposed, together with the requirement for further experimental investigation and waveform analysis.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"72 1","pages":"269 - 272"},"PeriodicalIF":0.0,"publicationDate":"2000-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88002603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Organic corrosion inhibitors for zinc pigment","authors":"B. M¨ller","doi":"10.1179/000705900101501407","DOIUrl":"https://doi.org/10.1179/000705900101501407","url":null,"abstract":"Abstract A severe problem with waterborne paints containing zinc pigments is hydrogen corrosion of the zinc in the aqueous alkaline paint media. The subject of the present study is the examination of corrosion inhibition of the zinc pigment in aqueous alkaline media by different high and low molecular weight organic inhibitors compared with that given by potassium dichromate. Potassium dichromate inhibits this corrosion reaction moderately, but a 4·0 mmol addition in 100 mL of the corrodent (1·2 wt-%) is required. Heterocyclic compounds are very poor corrosion inhibitors and less effective than potassium dichromate. Certain polymers with low acid numbers and low molecular weights and one particular epoxy ester resin are more effective inhibitors than potassium dichromate. Thus, some non-toxic polymers or paint resins can be considered as possible substitutes for toxic potassium dichromate.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"118 1","pages":"311 - 314"},"PeriodicalIF":0.0,"publicationDate":"2000-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80288899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. De Micheli, C. Barbosa, A. Andrade, S. Agostinho
{"title":"Electrochemical behaviour of 254SMO stainless steel in comparison with 316L stainless steel and Hastelloy C276 in HCl media","authors":"L. De Micheli, C. Barbosa, A. Andrade, S. Agostinho","doi":"10.1179/000705900101501371","DOIUrl":"https://doi.org/10.1179/000705900101501371","url":null,"abstract":"Abstract The electrochemical behaviour of 254SMO stainless steel in HCl solutions has been studied and compared with that observed for other alloys using open circuit potential measurements, potentiodynamic polarisation curves, and SEM analysis techniques. 254SMO does not display pitting corrosion at room temperature in HCl solutions having concentrations ≤5·0M. Its performance is comparable with that of Hastelloy C276 in HCl media in solutions of strength ≤1·0M. The critical pitting temperature for 254SMO exceeds 76°C in 3M HCl solutions.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"146 1","pages":"297 - 300"},"PeriodicalIF":0.0,"publicationDate":"2000-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88641172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Inhibitor effects of triazole derivatives on corrosion of mild steel in acidic media","authors":"F. Bentiss, M. Traisnel, M. Lagrenée","doi":"10.1179/000705900101501326","DOIUrl":"https://doi.org/10.1179/000705900101501326","url":null,"abstract":"Abstract The inhibitive action of triazoles on the corrosion of mild steel has been studied through weight loss and various electrochemical techniques. Results obtained show that these organic compounds are very good inhibitors. Triazoles are able to reduce the corrosion of steel more effectively in 1M HCl than in 0·5M H2 SO4 . Potentiodynamic polarisation studies clearly reveal the type of inhibitor. Changes in impedance parameters (the charge transfer resistance Rt and the double layer capacitance Cdl ) are related to adsorption of triazoles on the metal surface, leading to the formation of a protective film which grows with increasing exposure time. The adsorption of these inhibitors on the mild steel surface in both acids obeys the Langmuir adsorption isotherm. The comparative study of corrosion inhibition of triazole derivatives indicates that the efficiency of the 4-aminotriazole is greater than that of the 4H-triazole.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"49 1","pages":"315 - 320"},"PeriodicalIF":0.0,"publicationDate":"2000-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80700948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Inhibitive effect of some Schiff bases on corrosion of aluminium in hydrochloric acid solutions","authors":"A. Bansiwal, P. Anthony, S. P. Mathur","doi":"10.1179/000705900101501380","DOIUrl":"https://doi.org/10.1179/000705900101501380","url":null,"abstract":"Abstract Mass loss and thermometric methods have been used to study the inhibition of aluminium corrosion in HCl solution by four Schiff bases: 2-anisalidine-pyridine; 2-anisalidine-pyrimidine; 2-salicylidine-pyridine; and 2-salicylidine-pyrimidine. Values of inhibition efficiency obtained from the two methods are in good agreement and are dependent upon the concentrations of inhibitor and acid.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"55 1","pages":"301 - 303"},"PeriodicalIF":0.0,"publicationDate":"2000-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79045280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}