Menu
Search
Filters
Close
Menu

Acidification of the Electrolyte in the Carbon Steel/ Aluminum Alloys Galvanic Couple: Modeling and Experimental Study

Picture for Acidification of the Electrolyte in the Carbon Steel/ Aluminum Alloys Galvanic Couple: Modeling and Experimental Study
Available for download
Product Number: 51321-16334-SG
Author: A. Ortiz/ A. Ruiz-García/J. Genescá/R. Montoya
Publication Date: 2021
$0.00
$20.00
$20.00

An electrochemical  model  was  developed  to  predict  the  transient  distribution  of  species  generated  during corrosion of  carbon  steel  (CS)  /aluminum  alloy  (AA)  galvanic  couples  under  thin  NaCl  electrolyte  films  at room  temperature  (24  ºC).  Using  specific  geometrical  configurations,  strong  acidification of  the electrolyte,  localized  above  the  AA  surface  and  close  to the  carbon steel  electrode,  was  predicted. However,  a  small  zone evolved (also above  the AA  surface)  between  the  strong  acidified area and  the AA/CS  joint,  where the  pH  was  neutral  due  to the  OH-  production on the CS  surface.  Moderate acidification of  the  electrolyte  was  predicted  above  the  rest  of  the  AA  surface.  Both  diluted  and concentrated  electrolytes  were  taken into account.  Surprisingly,  the  less  concentrated  the  electrolyte,  the more  significant  the  drop  of  pH  on  top  of  the  AA  electrode.   Transient  experimental  measurements  were  achieved  with  the  help  of  an  innovative  setup,  and  findings corroborated  the  theoretical  predictions.  These  results  provide enough evidence to properly  discuss whether  such  an  acidification process  is  due  to  the production  of  intermediate aluminum  compounds  or by  the  fast  consumption  of  hydroxyl  ions  (OH-)  produced by  the  cathodic  reaction on  the  steel  surface.

Keywords:  galvanic  couples,  modeling,  aluminum  alloys,  aluminum  hydrolysis,  acid  corrosion. 

An electrochemical  model  was  developed  to  predict  the  transient  distribution  of  species  generated  during corrosion of  carbon  steel  (CS)  /aluminum  alloy  (AA)  galvanic  couples  under  thin  NaCl  electrolyte  films  at room  temperature  (24  ºC).  Using  specific  geometrical  configurations,  strong  acidification of  the electrolyte,  localized  above  the  AA  surface  and  close  to the  carbon steel  electrode,  was  predicted. However,  a  small  zone evolved (also above  the AA  surface)  between  the  strong  acidified area and  the AA/CS  joint,  where the  pH  was  neutral  due  to the  OH-  production on the CS  surface.  Moderate acidification of  the  electrolyte  was  predicted  above  the  rest  of  the  AA  surface.  Both  diluted  and concentrated  electrolytes  were  taken into account.  Surprisingly,  the  less  concentrated  the  electrolyte,  the more  significant  the  drop  of  pH  on  top  of  the  AA  electrode.   Transient  experimental  measurements  were  achieved  with  the  help  of  an  innovative  setup,  and  findings corroborated  the  theoretical  predictions.  These  results  provide enough evidence to properly  discuss whether  such  an  acidification process  is  due  to  the production  of  intermediate aluminum  compounds  or by  the  fast  consumption  of  hydroxyl  ions  (OH-)  produced by  the  cathodic  reaction on  the  steel  surface.

Keywords:  galvanic  couples,  modeling,  aluminum  alloys,  aluminum  hydrolysis,  acid  corrosion. 

Product tags
Also Purchased
Picture for Galvanic Series in Seawater as a Function of Temperature Oxygen Content and Chlorination
Available for download

51316-7058-Galvanic Series in Seawater as a Function of Temperature Oxygen Content and Chlorination

Product Number: 51316-7058-SG
ISBN: 7058 2016 CP
Author: Dominique Thierry
Publication Date: 2016
$20.00

In this work, the open circuit potential of different stainless steel grades as well as nickel based and copper based alloys has been systematically measured in seawater under different experimental conditions. In particular the effect of temperature, oxygen content and chlorination level have been studied.
Picture for 09274 Galvanic Corrosion Inhibition: Validation of Simple Laboratory Testing
Available for download

09274 Galvanic Corrosion Inhibition: Validation of Simple Laboratory Testing

Product Number: 51300-09274-SG
ISBN: 09274 2009 CP
Author: Luca A. Nolasco, Andrew MacDonald and Hongbin (Victor) Wang
Publication Date: 2009
$20.00
Picture for 08271 Effects of Oxygen, Temperature and Salinity on Carbon Steel Corrosion in Aqueous Solutions; Mo
Available for download

08271 Effects of Oxygen, Temperature and Salinity on Carbon Steel Corrosion in Aqueous Solutions; Model Predictions versus Laboratory Results

Product Number: 51300-08271-SG
ISBN: 08271 2008 CP
Author: Steven Grise and Brian Saldanha
Publication Date: 2008
$20.00

Corrosion of carbon steel materials in brine solutions.  Model results will be compared with literature data and lab experiments. Conditions will be limited to near neutral pH (5-9), temperature  from 22oC to 55oC, and O2 atmospheres up to 101.325 kPa.
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