British Corrosion Journal最新文献

{"title":"Corrosion resistance of borophosphate enamels in molten zinc","authors":"M. Zhou, J. Zhang, D. Shu, K. Li, H. Ni, W. Y. Zhang, B. Sun, J. Wang","doi":"10.1179/000705902225006651","DOIUrl":"https://doi.org/10.1179/000705902225006651","url":null,"abstract":"Abstract A study has been conducted of the resistance to corrosion in molten zinc of borophosphate enamels. The melting temperature of the enamels was adjusted by adding the carbonates of alkali metals and alkaline earth metals. Scanning electron microscopy was used to examine solidified interfaces between the enamels and the molten zinc. At low magnification (× 30) no evidence of components from the B2O3-P2O5 enamels was detected by electron probe in the industrially pure zinc near the interface with the enamel, but elemental Zn was found in the initially zinc free B2O3-P2O5 enamels. When the interface was examined at a magnification of 1000 times, it was confirmed by electron probe that no phosphorus from the borophosphate enamel was present in the zinc matrix at a position 60 μm from the interface. The results show that the borophosphate enamels are extremely resistant to corrosion in molten zinc.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"13 1","pages":"289 - 292"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81540409","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 news and views","authors":"","doi":"10.1179/bcj.2002.37.4.241","DOIUrl":"https://doi.org/10.1179/bcj.2002.37.4.241","url":null,"abstract":"","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"5 1","pages":"241 - 244"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81279294","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":"Crevice corrosion investigation on AA 6013: application of electrochemical noise analysis","authors":"M. Schneider, H. Pohl","doi":"10.1179/000705902225006714","DOIUrl":"https://doi.org/10.1179/000705902225006714","url":null,"abstract":"Abstract The aluminium alloy AA 6013 is of increasing significance with regard to the aircraft industry. In addition to its mechanical properties, corrosion resistance, especially against local corrosion phenomena (i.e. pitting corrosion and crevice corrosion), is very important in structural applications. In this work, the authors present the use of electrochemical noise analysis (ENA) in combination with a corrosion cell design, which was developed for the investigation of crevice corrosion. It is shown that ENA is a very useful technique for the early detection of crevice corrosion processes in the earliest stages of attack.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"8 1","pages":"298 - 304"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89838242","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":"Electrochemical and spectroscopic investigation of synergestic effects in corrosion inhibition of aluminium bronze Part 1 – In pure HCl","authors":"A. E. El Warraky, A. E. El Meleigy","doi":"10.1179/000705902225006688","DOIUrl":"https://doi.org/10.1179/000705902225006688","url":null,"abstract":"Abstract The synergistic inhibition of aluminium bronze corrosion by 4-phenyl semicarbazide hydrochloride (PSC) and the iodide ion in HCl of pH (1·8-2) at 60°C has been assessed by polarisation studies, Tafel plots, X-ray photoelectron spectroscopy and Auger electron spectroscopy. The addition of 0·01M KI to 0·01M PSC improved the inhibition efficiency from 86 to 94% owing to the formation of a CuI-PSC complex which is more compact, protective and hard than the film formed in the absence of iodide. The inner layer of this protective film contains a small amount of aluminium oxide, which increases the protective nature of the film and retards the dissolution of the underlying aluminium bronze.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"119 1","pages":"305 - 310"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79044243","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":"Zinc runoff from galvanised steel materials exposed in industrial/marine environment","authors":"J. Sullivan, D. Worsley","doi":"10.1179/000705902225006697","DOIUrl":"https://doi.org/10.1179/000705902225006697","url":null,"abstract":"Abstract An investigation has been carried out to assess the zinc runoff from a variety of galvanised materials over 16 months at the industrial/marine Port Talbot weathering site. Over 16 months of exposure, bare zinc, and Electrozinc have the highest levels of zinc runoff (4·38 and 4·20 g m-2) followed by general galvanised steel substrates, i.e. hot dip galvanised (HDG) steel (0·15 wt-%Al) (2·87 g m-2) and iron zinc intermetallic galvanised steel (galvanneal, 2·36 g m-2). Galvanneal (IZ) has a higher initial runoff rate than HDG due to the presence of iron/zinc intermetallic in the coating that promotes anodic zinc dissolution. The HDG has a more constant runoff rate that exceeds IZ after 7-8 months due to build up of corrosion products on the IZ surface. Aluminium/zinc alloy coated steels have a much lower runoff rate than general galvanised materials as the aluminium present in the structure provides a strongly protective oxide barrier coating improving corrosion resistance (Galfan 5 wt-%Al, 2·04 g m-2, and Z alutite 55 wt-%Al, 0·67 g m-2). Organically coated steels show relatively little zinc runoff (< 0·25 g m-2) indicating their effectiveness in preventing surface corrosion. Runoff levels measured do not exceed permissible levels of zinc for drinking water and the measured zinc runoff levels pose little threat to organisms if leached into soil. Using an accelerated laboratory test in which distilled water is sprayed onto specimen panels in a recirculatory system for 100 h a good correlation can be obtained with external exposure for up to 6 months exposure. For 12 months exposure iron zinc intermetallic galvanising (galvanneal) begins to become covered in a protective oxide layer, which cannot form under the conditions of the accelerated test. Despite this, the fit for most specimen types is excellent. Where the predictive test fails is when the galvanising layer is breached revealing an efficient iron cathode site. This occurs first for electrocoated zinc after 16 months exposure. Similar predictive results can be obtained using a scanning vibrating electrode technique (SVET) in a semiquantitative manner and an immersion electrolyte of 0·1 wt-%NaCl. Again the predictions are initially very accurate but following 12 months exposure the fit for specimens of electrozinc is poor due to the breaching of the galvanising layer.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"102 1","pages":"282 - 288"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88946743","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 of ferrous alloys in deep sea environments","authors":"R. Venkatesan, M. Venkatasamy, T. Bhaskaran, E. Dwarakadasa, M. Ravindran","doi":"10.1179/000705902225006633","DOIUrl":"https://doi.org/10.1179/000705902225006633","url":null,"abstract":"Abstract The deep sea corrosion of ferrous alloys that undergo uniform corrosion without forming a passive layer is related to the amount of dissolved ox ygen available in the sea water. The performance of some ferrous alloys at depths of 500, 1200, 3500, and 5100 m in the Indian Ocean has been studied. The results of atomic absorption spectroscopy have revealed that the corrosion product present on mild steel coupons is FeOOH. The results of experiments in shallow water have shown that micro- and macrobiological growths play a significant role in the corrosion of ferrous materials. However, in deeper waters, the absence of macrofouling was evident, and corrosion was not related to any biological product but mainly to the electrochemical reaction of these alloys with sea water. The results of morphological studies by SEM on the surfaces of ex posed specimens are also presented.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"148 1","pages":"257 - 266"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88993997","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 protection of 1008 carbon steel by hybrid coatings","authors":"G. Carbajal De la Torre, R. Nava Mendoza, M. Espinosa-Medina, A. Martínez-Villafañe, J. González-Rodríguez, V. Castaño","doi":"10.1179/000705902225006705","DOIUrl":"https://doi.org/10.1179/000705902225006705","url":null,"abstract":"Abstract Potentiodynamic polarisation curves have been used to evaluate the corrosion performance of 1008 carbon steel coated with hybrid (inorganic-organic) and mixed oxide coating systems deposited by dip coating. Several coatings have been prepared by the sol-gel method, using metallic alkox ides, such as tetraethylorthosilicate, aluminium isopropoxide, and zirconium propoxide, and polymers like allyl methacrylate (AMA) and polymethylmethacrylate (PMMA), together with zirconium dioxide (ZrO2) and silicon and aluminium oxides (SiO3-Al2O3). The aqueous test solutions included hydrochloric acid (HCl), sodium chloride (NaCl), and sulphuric acid (H 2SO4) at various concentrations (0·1, 0·5, and 1M). Scanning electron microscopy was used to examine the coatings following testing. The results have shown that SiO2-Al2O3 based coatings are not beneficial for corrosion protection in HCl, but are of value in the other aqueous media. In 1·0M HCl, the best protection was offered by a hybrid SiO2-ZrO2-poly(methylmethacrylate-allyl methacrylate) (P(MMA-AMA)) coating. In NaCl, the best results, were generally obtained with SiO2-Al2O3 and SiO2-ZrO2-P(MMA-AMA) coatings. Similarly, in H2SO4, the best results were generally displayed by the SiO2-Al2O3 and SiO2-ZrO2-P(MMA-AMA) coatings. The corrosion behaviour of the coatings is discussed in terms of the integrity and stability of the film.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"13 1","pages":"293 - 297"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77506481","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":"Localised corrosion behaviour of alloys 33 and 24 in simulated flue gas desulphurisation environment","authors":"N. Rajendran, G. Latha, S. Rajeswari","doi":"10.1179/000705902225006624","DOIUrl":"https://doi.org/10.1179/000705902225006624","url":null,"abstract":"Abstract Potentiodynamic anodic polarisation measurements have been carried out on type 316L stainless steel (as a reference material) and on alloys 33 and 24 in a simulated flue gas desulphurisation environment in order to assess the localised corrosion resistance. The results showed that the pitting corrosion resistance was higher in the case of alloys 33 and 24 than in the reference material owing to the higher contents of nitrogen, chromium, and molybdenum. An accelerated leaching study conducted on the alloys 33 and 24 showed only minor tendencies for the leaching of metal ions at various impressed potentials. Observations by SEM confirmed the lower tendency towards pitting of the alloys 33 and 24.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"484 1","pages":"276 - 281"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76373339","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":"Stress corrosion in copper–nickel alloys: influence of ammonia","authors":"D. Agarwal","doi":"10.1179/000705902225006660","DOIUrl":"https://doi.org/10.1179/000705902225006660","url":null,"abstract":"Abstract The test results from an earlier investigation by the author on the mechanical behaviour of a low nickel nickel-copper alloy exposed to a solution of 3·5%NaCl + 10%MgCl2 with and without ammonia indicated that the presence of 1% ammonia alters the failure mode and affects the load bearing capacity of the material. In the present investigation, further tests have been conducted on the same alloy to study its mechanical/corrosion behaviour on exposure to an aqueous solution of ammonia in comparison with exposure to a similar solution of ammonia containing 3·5%NaCl + 10%MgCl2. A constant displacement rate of 9·6 × 10-3 μ m s-1 was used and the concentration of ammonia was maintained at 5%. On exposure to the 5% aqueous ammonia solution, the mechanical properties of the alloy were degraded significantly and the material exhibited a brittle stress corrosion type of failure. However, on exposure to 5% ammonia in the presence of 3·5%NaCl + 10%MgCl2, there was less change in failure mode relative to that in air and a significant improvement in the mechanical properties of the material compared with those in aqueous ammonia. This indicates that the presence of MgCl2 and/or NaCl can be beneficial when low nickel copper alloys are exposed to ammonia. This paper presents the experimental results and observations from the recent tests, and discusses the relative roles of ammonia and NaCl/MgCl2 in determining the mechanical properties and modes of failure in a low nickel content copper-nickel alloy.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"77 1","pages":"267 - 275"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86092336","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":"Electrochemical behaviour of copper-nickel alloys in stagnant Na2CO3 solutions","authors":"A. Zaky, F. Assaf, S. S. Abd El Rehim, B. M. Mohamed","doi":"10.1179/000705902225006679","DOIUrl":"https://doi.org/10.1179/000705902225006679","url":null,"abstract":"Abstract The electrochemical behaviour of two copper-nickel alloys in solutions containing the carbonate ion has been investigated by cyclic voltammetric, potentiodynamic, and current/time transient techniques. Among the variables studied were alloy composition, stepwise increasing potential, scan rate, carbonate ion concentration and temperature. The composition of the compounds formed on the alloy surface during the anodic polarisation was characterised using X-ray diffraction analysis. The dissolution behaviour of the alloy consists of two potential regions separated by the critical potential Ecrit. The first potential region involves the selective dissolution of the more active constituent, nickel, and the appearance of one anodic peak A1 as a result of the formation of Ni(OH)2on the alloy surface. The second potential region relates to the simultaneous dissolution of copper and nickel. This region was characterised by the appearance of four anodic peaks A2, A3, A4, and A5, which are related to the formation of Cu2O, {CuO and Cu(OH)2}, CuCO3-Cu(OH)2 composite, and NiOOH, respectively. Potentiostatic current/time transients showed that the formation of Ni(OH)2, Cu2O, CuO, Cu(OH)2, CuCO3-Cu(OH)2 and NiOOH layers involves a nucleation and growth mechanism under diffusion control.","PeriodicalId":9349,"journal":{"name":"British Corrosion Journal","volume":"63 1","pages":"311 - 316"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78751000","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}