Untitled

Cook, Dianne; Oh, Seungjae; Balasubramanian, Rama; Yamashita, Masato

doi:10.1023/a:1012685320582

Cited by 96 publications

(38 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Various spectroscopic studies such as X-ray diffraction, [1][2][3] Raman, 4,5) infrared 6,7) and Mössbauer [8][9][10] spectroscopies has been carried out to understand the protective ability of the rust layer in terms of its structure. These studies revealed that the protective rust layer of weathering steel has a doublelayer structure and its inner layer is mainly composed of ultrafine crystals of -FeOOH containing small amounts of Cr.…”

Section: Introductionmentioning

confidence: 99%

Structure Analysis of Cation Selective Cr-goethite as Protective Rust of Weathering Steel

et al. 2005

View full text Add to dashboard Cite

We have performed extended X-ray absorption fine structure (EXAFS) analysis for artificial Cr-goethite to elucidate the local structure around Cr in Cr-goethite. The spectra were obtained using synchrotron radiation X-rays at the Photon Factory in Tsukuba. The first shell contributions were isolated by Fourier filtering the EXAFS data, and the inverse Fourier transformed single-shell data were analyzed using a curve fitting method. The results show that Cr is coordinated with (7 AE 1) O 2À ions. The protective characteristics of the Cr-goethite protective rust layer on weathering steel can be interpreted in terms of the O 2À coordination around Cr 3þ resulting in the creation of negative fixed charge in the Cr-goethite particles.

show abstract

Section: Introductionmentioning

confidence: 99%

Structure Analysis of Cation Selective Cr-goethite as Protective Rust of Weathering Steel

et al. 2005

View full text Add to dashboard Cite

show abstract

“…The cause of this property is a protective rust layer formed on the surface of weathering steel, which can prevent the penetration of water and corrosive ions from the atmosphere. Structural studies by various spectroscopic methods, such as X-ray diffraction, [1][2][3] Raman, 4,5) infrared 6,7) and Mössbauer [8][9][10] spectroscopies, revealed that the protective rust layer has a double-layer structure. The inner layer mainly consists of ultrafine particles of Cr-goethite, which is -FeOOH containing a small amount of Cr.…”

Section: Introductionmentioning

confidence: 99%

Characterization of Rust Layer Formed on Fe, Fe-Ni and Fe-Cr Alloys Exposed to Cl-Rich Environment by Cl and Fe K-Edge XANES Measurements

et al. 2005

View full text Add to dashboard Cite

Chloride in atmosphere considerably reduces the corrosion resistance of conventional weathering steel containing a small amount of Cr. Ni is an effective anticorrosive element for improving the corrosion resistance of steel in a Cl-rich environment. In order to clarify the structure of the protective rust layer of weathering steel, Cl and Fe K-edge X-ray absorption near edge structure (XANES) spectra of atmospheric corrosion products (rust) formed on Fe, Fe-Ni and Fe-Cr alloys exposed to Cl-rich atmosphere were measured. The Fe K-XANES measurements enable the characterization of a mixture of iron oxides such as rust. The chemical composition of the rust was determined by performing pattern fitting of the measured spectra. All the rust is composed mainly of goethite, akaganéite, lepidocrocite and magnetite. Among these iron oxides, akaganéite in particular is the major component in the rust. Additionally, the amount of akaganéite in the rust of Fe-Ni alloy is much greater than that in rust of Fe-Cr alloy. Akaganéite is generally considered to facilitate the corrosion of steel, but our results indicate that akaganéite in the rust of Fe-Ni alloy is quantitatively different from that in rust of Fe-Cr alloy and does not facilitate the corrosion of steel. The shoulder peak observed in Cl K-XANES spectra reveals that the rust contains a chloride other than akaganéite. The energy of the shoulder peak does not correspond to that of any well-known chlorides. In the measured spectra, there is no proof that Cl, by combining with the alloying element, inhibits the alloying element from acting in corrosion resistance. The shoulder peak appears only when the content of the alloying element is lower than a certain value. This suggests that the generation of the unidentified chloride is related to the corrosion rate of steel.

show abstract

“…The structure of the protective rust layers has been studied by various spectroscopies such as X-ray diffraction, [1][2][3] Raman, 4,5) infrared 6,7) and Mössbauer [8][9][10] spectroscopies. Those studies revealed that the protective rust layer consists of ultrafine crystals of ferric oxyhydroxides and the protective effect is derived from the dense aggregation of ultrafine goethite, -FeOOH, which contains a certain amount of Cr.…”

Section: Introductionmentioning

confidence: 99%

Nanostructure of Protective Rust Layer on Weathering Steel Examined Using Synchrotron Radiation X-rays

et al. 2004

View full text Add to dashboard Cite

The X-ray absorption fine structure (XAFS) spectrum of pure goethite around the Fe K absorption edge and that of the protective rust layer formed on weathering steel exposed for 17 years in an atmospheric environment around the Cr K edge, have been examined using synchrotron radiation X-rays. It was found that the rust layer on the weathering steel mainly consisted of Cr-goethite. By examining the fine structure at the Cr K edge and the Fe K edge, we concluded that Cr 3þ in the rust layer is coordinated with O 2À and is positioned in the double chains of vacant sites in the network of FeO 3 (OH) 3 octahedra in the goethite crystal. This Cr 3þ site indicates that the protective effect of the rust layer is due to the dense aggregation of fine crystals of Cr-goethite with cation selectivity.

show abstract

Untitled

Cited by 96 publications

References 2 publications

Structure Analysis of Cation Selective Cr-goethite as Protective Rust of Weathering Steel

Structure Analysis of Cation Selective Cr-goethite as Protective Rust of Weathering Steel

Characterization of Rust Layer Formed on Fe, Fe-Ni and Fe-Cr Alloys Exposed to Cl-Rich Environment by Cl and Fe K-Edge XANES Measurements

Nanostructure of Protective Rust Layer on Weathering Steel Examined Using Synchrotron Radiation X-rays

Contact Info

Product

Resources

About