Menu
Search
Filters
Close
Menu

Save 20% on select titles with code HIDDEN24 - Shop The Sale Now

Comparative Evaluation of Four Viscoelastic Materials for Coating Patch Repairs

Picture for Comparative Evaluation of Four Viscoelastic Materials for Coating Patch Repairs
Available for download
Product Number: 51321-16444-SG
Author: Haralampos Tsaprailis/ Jiajun (Jeff) Liang/Shan (Sherry) Rao
Publication Date: 2021
$0.00
$20.00
$20.00

For the viscous-elastic coating materials, the most prominent claims by the coating manufacturers are impermeable to water, self-healing, low or no undercreep (rust creepage), and no disbondment. These aspects were examined by a comparative evaluation on the performance characteristics of four viscoelastic materials using a specially designed test program. The tests were carried out in 3% NaCl water immersion conditions at 4, 25, and 65ºC for 100 days, coupled with the use of electrochemical impedance spectroscopy (EIS) to periodically monitor the progress of water permeation and interfacial corrosion behavior of the undamaged materials. Water uptake derived from EIS modeling confirmed that all four viscoelastic materials had higher water permeability at higher temperature; however, peel adhesion test revealed lower adhesion on some materials after 100 days immersion at lower test temperatures. With the EIS technique, in-depth data interpretation leads to a proper understanding of the probable mechanism of lower adhesion at lower temperatures. The resistance to undercreep was also investigated on the test materials with an artificial defect used to mimic mechanical damage to coating. The examination results proved negligible undercreep but significant delamination at 65 ºC was observed on all four test materials. Cathodic disbondment testing also confirmed that viscoelastic materials will disbond under cathodic protection, but the extent of disbondment will vary between the different viscoelastic test materials.

Key words: viscous-elastic coating technology, comparative evaluation, water immersion, EIS, modeling, peel adhesion, underfilm corrosion, cathodic delamination, cathodic disbondment

For the viscous-elastic coating materials, the most prominent claims by the coating manufacturers are impermeable to water, self-healing, low or no undercreep (rust creepage), and no disbondment. These aspects were examined by a comparative evaluation on the performance characteristics of four viscoelastic materials using a specially designed test program. The tests were carried out in 3% NaCl water immersion conditions at 4, 25, and 65ºC for 100 days, coupled with the use of electrochemical impedance spectroscopy (EIS) to periodically monitor the progress of water permeation and interfacial corrosion behavior of the undamaged materials. Water uptake derived from EIS modeling confirmed that all four viscoelastic materials had higher water permeability at higher temperature; however, peel adhesion test revealed lower adhesion on some materials after 100 days immersion at lower test temperatures. With the EIS technique, in-depth data interpretation leads to a proper understanding of the probable mechanism of lower adhesion at lower temperatures. The resistance to undercreep was also investigated on the test materials with an artificial defect used to mimic mechanical damage to coating. The examination results proved negligible undercreep but significant delamination at 65 ºC was observed on all four test materials. Cathodic disbondment testing also confirmed that viscoelastic materials will disbond under cathodic protection, but the extent of disbondment will vary between the different viscoelastic test materials.

Key words: viscous-elastic coating technology, comparative evaluation, water immersion, EIS, modeling, peel adhesion, underfilm corrosion, cathodic delamination, cathodic disbondment

Product tags
Also Purchased
Insights into the Consideration and Selection of Viscoelastic Materials for Potential Use in Field Patch Application
Available for download

Insights into the Consideration and Selection of Viscoelastic Materials for Potential Use in Field Patch Application

Product Number: 51220-294-SG
Author: Haralampos Tsaprailis, Jiajun (Jeff) Liang, Shan (Sherry) Rao
Publication Date: 2020
$20.00

The intention of the study is to explore potential field maintenance products with service temperature ranges of 0 to 65°C for patch application, including patch repairing and to provide corrosion protection for irregularly shaped components, such as fittings and electrical connection to pipe (e.g., cadweld). Viscoelastic materials were selected as potential candidates due to their inherent features of cold-flow capability, low water permeability, easy application (by hand and directly applied to surface), and compatibility with a variety of existing pipeline coatings. 
Picture for 10042 Use of 100% Self-Healing Fully Amorphous Visco-Elastic Coating Against Corrosion
Available for download

10042 Use of 100% Self-Healing Fully Amorphous Visco-Elastic Coating Against Corrosion

Product Number: 51300-10042-SG
ISBN: 10042 2010 CP
Author: Jan Frederik Doddema
Publication Date: 2010
$20.00
Picture for 03710 INTERFERENCE TESTING AND CASE HISTORIES
Available for download

03710 INTERFERENCE TESTING AND CASE HISTORIES

Product Number: 51300-03710-SG
ISBN: 03710 2003 CP
Author: Jeffrey L. Didas
Publication Date: 2003
$20.00

Interference Testing is a task learned through education and experience and is one of the basic skills of Cathodic Protection Personnel. This paper will discuss interference testing and present some case histories, of basic static interference situations and the mitigation methods used.
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