Server maintenance is scheduled for Saturday, December 21st between 6am-10am CST.

During that time, parts of our website will be affected until maintenance is completed. Thank you for your patience.

Menu
Search
Filters
Close
Menu

Effect of Early and Late Presence of Sulfate Ions on Steel Corrosion Development in Alkaline Solution

Picture for Effect of Early and Late Presence of Sulfate Ions on Steel Corrosion Development in Alkaline Solution
Available for download


Effective highway bridge design in terms of strength, service, and economy can be made using prestressed concrete including post-tensioned (PT) construction.1-2 Bonded PT bridge designs incorporate high strength steel strand within tendon ducts and encapsulated with cementitious grout.3-4 The grout provides a protective barrier layer for the steel by preventing direct exposure to the external environment as well as facilitating the natural development of a thin passive oxide layer on the steel surface in presence of the high grout pore water pH.

Product Number: 51323-18957-SG
Author: Dorsa Fatemeh Sarab, Samanbar Permeh, Kingsley Lau
Publication Date: 2023
$0.00
$20.00
$20.00

In post-tensioned (PT) concrete, grout is used to protect the steel strand by providing a physical barrier to external moisture and contaminants and allowing for a protective passive film. However, corrosion failures of tendons associated with deficient grout materials occurred in Florida. Recent works demonstrated that elevated sulfate levels in alkaline environments can promote steel corrosion. However, testing in concrete materials sometimes did not reveal the role of sulfates. The purpose of the work here was to identify the influence of early and late sulfate ions presence on the formation of the passive film in alkaline solution. Steel specimens were exposed to saturated calcium hydroxide solution with sulfate levels ranging from 10,000 to 100,000 ppm. Electrochemical tests including open-circuit potential (OCP), linear polarization resistance (LPR), and anodic potentiodynamic polarization scans were made to identify conditions for steel passivation and corrosion initiation. In tests with early addition of sulfate, results indicated higher corrosion activity with greater sulfate concentration. Late sulfate additions after steel prepassivation showed less significant corrosion development below 30,000 ppm and relatively less corrosion in comparison to the early sulfate addition case. It was apparent that the sulfate ion concentrations in deficient grout can impair steel passivity but later sulfate presence due to external contamination would have less aggravating effect on corrosion development.


In post-tensioned (PT) concrete, grout is used to protect the steel strand by providing a physical barrier to external moisture and contaminants and allowing for a protective passive film. However, corrosion failures of tendons associated with deficient grout materials occurred in Florida. Recent works demonstrated that elevated sulfate levels in alkaline environments can promote steel corrosion. However, testing in concrete materials sometimes did not reveal the role of sulfates. The purpose of the work here was to identify the influence of early and late sulfate ions presence on the formation of the passive film in alkaline solution. Steel specimens were exposed to saturated calcium hydroxide solution with sulfate levels ranging from 10,000 to 100,000 ppm. Electrochemical tests including open-circuit potential (OCP), linear polarization resistance (LPR), and anodic potentiodynamic polarization scans were made to identify conditions for steel passivation and corrosion initiation. In tests with early addition of sulfate, results indicated higher corrosion activity with greater sulfate concentration. Late sulfate additions after steel prepassivation showed less significant corrosion development below 30,000 ppm and relatively less corrosion in comparison to the early sulfate addition case. It was apparent that the sulfate ion concentrations in deficient grout can impair steel passivity but later sulfate presence due to external contamination would have less aggravating effect on corrosion development.


Product tags
Also Purchased
Picture for Revisiting Alloy K-500 with Improved Performance Limits for Short and Long-Term Subterranean Applications
Available for download

Revisiting Alloy K-500 with Improved Performance Limits for Short and Long-Term Subterranean Applications

Product Number: 51323-18787-SG
Author: Manuel Marya
Publication Date: 2023
$20.00

Alloy K-500 (UNS N05500) is concomitantly a centurial material and the very first precipitation-strengthened nickel-based alloy, then developed in the 1920s by the newly-formed International Nickel Company, or Inco. 
Derived from Monel 400 (UNS N04400) that was invented in 1901, Alloy K-500 shares many of the same corrosion and tribological characteristics.  Being a pioneer alloy with so-called “stain-less” characteristics, Alloy
K-500 also established itself as the first high-strength oilfield nickel alloy, having survived sour service conditions exceeding the capabilities of the low-alloy steels of the time. From early naval propeller shaft applications to
general cross-industrial uses, Alloy K-500 has always been considered a corrosion-resistant alloy, or CRA. For instance, it has been included in the NACE MR1075 document right from the first 1975 edition. 
Picture for Field Testing of Self-Healing Metallic Coatings for Internal Corrosion Protection of Natural Gas Pipelines
Available for download

Field Testing of Self-Healing Metallic Coatings for Internal Corrosion Protection of Natural Gas Pipelines

Product Number: 51323-18857-SG
Author: Zineb Belarbi, Ömer N. Doğan, Patrick Carr, Richard E. Chinn, Julius Samson
Publication Date: 2023
$20.00

Natural gas pipelines are subject to internal corrosion. Internal corrosion of steel pipelines can cause natural gas leakage, leading to wasted energy, explosion hazards, and methane emissions. The U.S. Department of Transport reported numerous case histories of corrosion problems and failures in wet gas pipelines. The National Energy Technology Laboratory (NETL) performed an incident survey from 2010 through 2018 and found that 112 (12%) of these incidents in the U.S. transmission lines were caused by internal corrosion.
Picture for Investigation of the Pitting Corrosion Behavior of Austenitic Stainless Steel UNS S20910 Correlated to its Microstructural Condition
Available for download

Investigation of the Pitting Corrosion Behavior of Austenitic Stainless Steel UNS S20910 Correlated to its Microstructural Condition

Product Number: 51323-18877-SG
Author: Helmuth Sarmiento Klapper, Julia Ditmann, Clara Herrera, Merlin Seifert
Publication Date: 2023
$20.00

During drilling operations, the components in the drill string including the bottom hole assembly (BHA) remains in permanent contact with the drilling fluid. Therefore, besides non-magnetic properties and high strength the corrosion resistance of the materials utilized for the BHA plays a decisive role specially in applications involving harsh environments. In fact, strain-hardened CrMn-austenitic steels commonly used in directional drilling technology show a high susceptibility to pitting corrosion and environmentally assisted cracking in drilling fluids with a high chloride (Cl-) content at elevated temperatures.
Categories
Industry
Recently viewed
Popular tags
View all

Association for Materials Protection and Performance

© AMPP All Rights Reserved.
Membership Terms of Content Use
Contact Customer Support