Structure Analysis of Cation Selective Cr-goethite as Protective Rust of Weathering Steel
نویسندگان
چکیده
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 1) O ions. The protective characteristics of the Cr-goethite protective rust layer on weathering steel can be interpreted in terms of the O coordination around Cr3þ resulting in the creation of negative fixed charge in the Cr-goethite particles.
منابع مشابه
Rust Formation Mechanism on Low Alloy Steels after Exposure Test in High Cl− and High SOx Environment
Exposure tests were performed on low alloy steels in high Cl- and high SOx environment, and the structure of the rust were analyzed by TEM (Transmission Electron Microscopy) and Raman Spectroscopy. In the exposure test site, the concentrations of Cl- and SOx were found to be high, which caused the corrosion of the steels. The conventional weathering steel (SMA: 0.6% Cr-0.4% Cu-Fe) showed higher...
متن کاملAn Active Coating and New Protection Technology for Weathering Steel Structures in Chloride Containing Environments
A new coating that allows formation of the correct protective patina on weathering steel structures located in regions of high chlorine and/or high time-of–wetness, has been developed. The coating controls the time-of-wetness at the steel surface, allowing correct wet/dry cycling required for protective patina formation. It also binds chloride ions, and prevents them from reaching the steel sur...
متن کاملCharacterization of Rust Layers on Weathering Steels Air-Exposed for a Long Period
Several weathering steels and a plain carbon steel exposed to atmosphere for 17 years at Yokkaichi (at a coastal and industrial region) and Mikuni Pass (at a rural region) in Japan were analyzed and compared to find effects of environments on the formed rusts. Specimens were examined with electron probe microanalysis (EPMA), X-ray diffraction (XRD) and transmission electron microscope (TEM). Th...
متن کاملCorrosion Monitoring of Weathering Steel in a Simulated Coastal-Industrial Environment
The atmospheres in many cities along the coastal lines in the world have been rapidly changed to coastal-industrial atmosphere. Hence, it is vital to investigate the corrosion behavior of steel exposed to this kind of environment. In this present study, Electrochemical Impedance Spectrography (EIS) and film thickness measurement were applied to monitor the corrosion behavior of weathering steel...
متن کاملCorrosion resistance of Si-Al-bearing ultrafine-grained weathering steel.
In the Ultra-steel project at the National Institute for Materials Science (NIMS), which run from 1996 to 2005, high-Si-Al-content ultrafine-grained (UFG) weathering steel was developed by grain refinement and weathering guidance. It was found that this steel has excellent strength, toughness and corrosion resistance. Samples were prepared by multi pass warm rolling at temperatures between 773 ...
متن کامل