BS ISO 23449:2020

What is ISO 23449 about? 

ISO 23449 is a safety standard on metals and alloys. 

ISO 23449 can be used as a powerful tool for studying the initiation and propagation processes of localized corrosion. ISO 23449 specifies the methodology of using multielectrode arrays for the measurement of the corrosion, especially localized corrosion, of metals and alloys. ISO 23449 can be used as a powerful tool for studying the initiation and propagation processes of localized corrosion. ISO 23449 is also a useful tool for long-term corrosion monitoring in the field, especially for localized corrosion, and for obtaining high throughput results for the evaluation of metals with different compositions and/or physical properties in different environments and the screening of a large number of inhibitors.  

Additionally, the galvanic coupling current and potential distribution of dissimilar metal parings can be assessed by multielectrode arrays. Multielectrode arrays can be implemented in full-immersion, thin-film, spray, and alternating wet-dry cycle exposures. 

NOTE: ISO 23449 is not intended to be used for measurements of corrosion caused by a non-electrochemical mechanism. 

Who is ISO 23449 for?  

ISO 23449 on the multielectrode arrays for corrosion measurement is relevant to: 

• Corrosion engineers 
• Metal laboratories 
• Manufacturers of alloys 
• Electrochemical engineers 
• Chemical processing industries 
• Corrosion testing labs 

Why should you use ISO 23449? 

Multielectrode array technology has been used to study electrochemical behaviours and the localized corrosion of metals and alloys. 

It has been demonstrated that multielectrode arrays are powerful tools for studying the spatiotemporal behaviour of metals in laboratories. Multielectrode arrays are also used as high throughput probes for studying the statistical behaviour of metal corrosion and for the evaluation of inhibitors. ISO 23449 is designed to outline the requirements and procedures for conducting corrosion measurements using multielectrode arrays. The currents of the electrodes composing the array can be measured individually. It is possible to measure the potentials of each individual electrode, of a selected group of electrodes, or the totality of the electrodes if they are coupled. 

Multielectrode arrays can also be used in many other applications, including the following: 

• Assessing the electrochemical behaviour of material across various weld zones. As the material is welded, various zones are created that differ in properties due to the differences in cooling rates and heat treatment from welding. These differences in properties are spatially dependent and can be assessed with multielectrode arrays 
• Understanding the galvanic throwing power of sacrificial anodes by measuring the coupling current and potential distributions between the sacrificial anode and the surrounding electrodes being cathodically protected 
• Studying the effect of corrosion inhibitors on reducing the anodic or cathodic reaction rates at an electrode interface, especially for spatial-temporal release from inhibitor-containing coatings 

Overall, ISO 23449 is useful as it assists with the corrosion that occurs at different rates over a metal surface where there is a localized surplus of net anodic or net cathodic rates such that a localized area does not exhibit charge neutrality and electrons flow within the metal from the anodic-dominant areas to the cathodic-dominant areas.