{"title":"高钙质海水中低碳钢的中短期腐蚀:碳酸钙浓度、试样取向和营养物添加的影响","authors":"Peter J. Richardson, R. Melchers","doi":"10.5006/4453","DOIUrl":null,"url":null,"abstract":"\n Mild steels exposed to marine immersion conditions in which carbonate solubilities are exceeded, leading to deposition of calcareous material, have been shown to exhibit much reduced corrosion rates compared with corrosion under conditions in which there is no exceedance of solubility limits and therefore no calcareous deposition. However, the differences in corrosion including the potential effect of MIC in these conditions have not been examined systematically in the literature. The study reported herein involves short- to medium-term marine immersion exposures (up to 18 months) of mild steel coupons in natural seawater (control) and in environments using the same seawater source dosed with: 1) CaCO3, acting as an inorganic particulate suspension representative of that encountered in seawater with elevated calcareous content, and 2) a nitrate salt, acting as an industrial pollutant and bacterial nutrient source. The results show the extent to which the deposition of particulate CaCO3 from suspension in seawater onto and into the rusts reduces the rate of corrosion of mild steel; a rate that was found to be dependent on the coupon orientation within the seawater. Coupons which were permanently buried beneath a cap of settled CaCO3 particles exhibited a 70% reduction in corrosion rate compared with the representative control coupons. The results also show that for these exposure durations and conditions, while IRB and SRB bacterial species were identified in high concentrations (respectively ~1 × 106 cfu/g and ~1 × 102 to 4 × 106 cfu/g, depending on coupon orientation) within the rust products themselves after 18 months of exposure, there was no clear evidence of MIC. These findings indicate that short and medium term (non-accelerated) studies of MIC for mild steel are insufficient or even mis-leading for the prediction of long-term corrosion rates in these environments.","PeriodicalId":10717,"journal":{"name":"Corrosion","volume":"9 2","pages":""},"PeriodicalIF":1.1000,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Short- to medium-term corrosion of mild steel in highly calcareous seawaters: effects of calcium carbonate concentration, coupon orientation and nutrient addition\",\"authors\":\"Peter J. Richardson, R. Melchers\",\"doi\":\"10.5006/4453\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"\\n Mild steels exposed to marine immersion conditions in which carbonate solubilities are exceeded, leading to deposition of calcareous material, have been shown to exhibit much reduced corrosion rates compared with corrosion under conditions in which there is no exceedance of solubility limits and therefore no calcareous deposition. However, the differences in corrosion including the potential effect of MIC in these conditions have not been examined systematically in the literature. The study reported herein involves short- to medium-term marine immersion exposures (up to 18 months) of mild steel coupons in natural seawater (control) and in environments using the same seawater source dosed with: 1) CaCO3, acting as an inorganic particulate suspension representative of that encountered in seawater with elevated calcareous content, and 2) a nitrate salt, acting as an industrial pollutant and bacterial nutrient source. The results show the extent to which the deposition of particulate CaCO3 from suspension in seawater onto and into the rusts reduces the rate of corrosion of mild steel; a rate that was found to be dependent on the coupon orientation within the seawater. Coupons which were permanently buried beneath a cap of settled CaCO3 particles exhibited a 70% reduction in corrosion rate compared with the representative control coupons. The results also show that for these exposure durations and conditions, while IRB and SRB bacterial species were identified in high concentrations (respectively ~1 × 106 cfu/g and ~1 × 102 to 4 × 106 cfu/g, depending on coupon orientation) within the rust products themselves after 18 months of exposure, there was no clear evidence of MIC. These findings indicate that short and medium term (non-accelerated) studies of MIC for mild steel are insufficient or even mis-leading for the prediction of long-term corrosion rates in these environments.\",\"PeriodicalId\":10717,\"journal\":{\"name\":\"Corrosion\",\"volume\":\"9 2\",\"pages\":\"\"},\"PeriodicalIF\":1.1000,\"publicationDate\":\"2024-01-09\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Corrosion\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://doi.org/10.5006/4453\",\"RegionNum\":4,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"MATERIALS SCIENCE, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Corrosion","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.5006/4453","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
Short- to medium-term corrosion of mild steel in highly calcareous seawaters: effects of calcium carbonate concentration, coupon orientation and nutrient addition
Mild steels exposed to marine immersion conditions in which carbonate solubilities are exceeded, leading to deposition of calcareous material, have been shown to exhibit much reduced corrosion rates compared with corrosion under conditions in which there is no exceedance of solubility limits and therefore no calcareous deposition. However, the differences in corrosion including the potential effect of MIC in these conditions have not been examined systematically in the literature. The study reported herein involves short- to medium-term marine immersion exposures (up to 18 months) of mild steel coupons in natural seawater (control) and in environments using the same seawater source dosed with: 1) CaCO3, acting as an inorganic particulate suspension representative of that encountered in seawater with elevated calcareous content, and 2) a nitrate salt, acting as an industrial pollutant and bacterial nutrient source. The results show the extent to which the deposition of particulate CaCO3 from suspension in seawater onto and into the rusts reduces the rate of corrosion of mild steel; a rate that was found to be dependent on the coupon orientation within the seawater. Coupons which were permanently buried beneath a cap of settled CaCO3 particles exhibited a 70% reduction in corrosion rate compared with the representative control coupons. The results also show that for these exposure durations and conditions, while IRB and SRB bacterial species were identified in high concentrations (respectively ~1 × 106 cfu/g and ~1 × 102 to 4 × 106 cfu/g, depending on coupon orientation) within the rust products themselves after 18 months of exposure, there was no clear evidence of MIC. These findings indicate that short and medium term (non-accelerated) studies of MIC for mild steel are insufficient or even mis-leading for the prediction of long-term corrosion rates in these environments.
期刊介绍:
CORROSION is the premier research journal featuring peer-reviewed technical articles from the world’s top researchers and provides a permanent record of progress in the science and technology of corrosion prevention and control. The scope of the journal includes the latest developments in areas of corrosion metallurgy, mechanisms, predictors, cracking (sulfide stress, stress corrosion, hydrogen-induced), passivation, and CO2 corrosion.
70+ years and over 7,100 peer-reviewed articles with advances in corrosion science and engineering have been published in CORROSION. The journal publishes seven article types – original articles, invited critical reviews, technical notes, corrosion communications fast-tracked for rapid publication, special research topic issues, research letters of yearly annual conference student poster sessions, and scientific investigations of field corrosion processes. CORROSION, the Journal of Science and Engineering, serves as an important communication platform for academics, researchers, technical libraries, and universities.
Articles considered for CORROSION should have significant permanent value and should accomplish at least one of the following objectives:
• Contribute awareness of corrosion phenomena,
• Advance understanding of fundamental process, and/or
• Further the knowledge of techniques and practices used to reduce corrosion.