Microfabrication methods have been used to construct crevice formers of rigorously controlled gap and length. These have been used to study the IR-controlled crevice corrosion of Ni200 in 0.5 M H2SO4 to determine the effect of crevice gap ~G! on the position of the accelerated attack (xcrit) within the crevice. The experimental results were then compared to the results of computational studies....

A comprehensive fireside corrosion project was undertaken to better understand the corrosion mechanisms operating on the lower furnace walls and superheaters in modern coal-fired utility boilers. Eight U.S. coals commonly burned in boilers have been selected to represent a wide range of coal chemistry. These coals will be burned in a pilot-scale combustion facility to closely simulate the actua...

This paper aims to present the newly designed acoustic emission AE instrument for the in-situ monitoring of corrosion damages of aircraft structures. The work was theoretically based on the combination of modal AE theory and AE parameter analysis technique. Previous research had shown that identification of corrosion AE and background noise by modal acoustic emission(MAE) technique was possible...

The effect of an inert solid deposit on uniform CO2 corrosion of mild steel is modeled based on a mechanistic electrochemical CO2 corrosion model. Laboratory testing has shown that the dominant factors introduced by the inert solids deposit are related to surface coverage, where both anodic and cathodic reaction rates are decreased because of less active surface area being exposed. The inert so...

Oil well are periodically acidized for enhancing oil flow. Inhibited hydrochloric acid is used during acidization to prevent corrosion of N80 or J55 steel. In the present work authors have surveyed literature on acidizing corrosion inhibitors and the salient features of research work carried out by the authors have also been highlighted.

Crevice corrosion material loss is often most severe at intermediate distances into the crevice. This intermediate attack can be rationalized using the ohmic drop model of Pickering if and only if the material in question exhibits active/passive behavior in the crevice environment. Conventional theories that ascribe control of crevice corrosion to chemical changes exclusively cannot rationalize...

Pitting corrosion is localized accelerated dissolution of metal that occurs as a result of a breakdown of the otherwise protective passive film on the metal surface. This paper provides an overview of the critical factors influencing the pitting corrosion of metals. The phenomenology of pitting corrosion is discussed, including the effects of alloy composition, environment, potential, and tempe...

An integrated multiphase flow and corrosion prediction package was tested by comparing it’s performance with data obtained from the field. The comparisons indicated a satisfactory performance, even for the situations where incomplete information was available about the field cases. The results have shown that the effect of traces of H2S on CO2 corrosion needs to be given particular care when ma...

The dynamic process of crevice corrosion during anodic dissolution of a crevice electrode in a 5.0 mmol dm-3 NaCl solution has been studied by digital holographic reconstruction. Digital holographic reconstruction has been proved to be an effective and in situ technique to detect the changes in the solution concentration because useful and direct information can be obtained from the three-dimen...

DISCLAIMER This report, prepared in cooperation with the University of Rhode Island Transportation Center, does not constitute a standard, specification, or regulation. The contents of this report reflect the views of the author(s) who is (are) responsible for the facts and the accuracy of the data presented herein. This document is disseminated under the sponsorship of the Department of Transp...