ISO/TC 35/SC 9/WG 29 - Electrochemical methods

ISO 16773-4:2017 gives some typical examples of impedance spectra of polymer-coated and uncoated specimens (see Annex A). Some guidance on interpretation of such spectra is also given. Further examples of spectra of low-impedance systems (range from, e.g. 10 Ω to 1 000 Ω) are given in ISO/TR 16208 and in ASTM G106. ISO 16773‑2 gives guidelines for optimizing the collection of EIS data with focus on high-impedance systems.

ISO 16773-2:2016 gives guidelines for optimizing the collection of EIS data with focus on high-impedance systems. High impedance in the context of intact coatings refers to systems with an impedance greater than 109 Ω⋅cm2. This does not preclude measurements on systems with lower impedance. For uncoated samples extra information can be found in ISO/TR 16208. ISO 16773-2:2016 deals with the following: - instrumental set-up: requirements and pit-falls; - data validation: checking the measurement range and the accuracy of the data; - performing an EIS measurement: specimen considerations and instrumental parameters; - the experimental results: different methods of presenting EIS data. These guidelines are intended to ensure the acquisition of EIS data that can be used to study the performance of the specimen. This part of ISO 16773 does not give guidelines for the interpretation of the data.

ISO 16773-1:2016 defines terms for electrochemical impedance spectroscopy (EIS) for use in the other parts of ISO 16773.

ISO 16773-3:2016 specifies a procedure for the evaluation of the experimental set-up used for carrying out EIS on high-impedance coated samples. For this purpose, dummy cells are used to simulate high-impedance coated samples. On the basis of the equivalent circuits described, this part of ISO 16773 gives guidelines for the use of dummy cells to increase confidence in the test protocol, including making measurements, curve fitting and data presentation. NOTE Due to the nature of the measurements, investigations of high-impedance coated samples are more susceptible to artefacts coming from electromagnetic interferences. Therefore, this part of ISO 16773 considers the aspects for measuring high-impedance samples by using appropriate dummy cells in a Faraday cage. However, most manufacturers offer complementary dummy cells in the low and medium impedance range. This allows checking the setup in the respective low impedance range.

ISO 17463:2014 gives guidelines on how to perform accelerated cyclic electrochemical technique (ACET) with organic protective coatings on metals. ISO 17463:2014 specifies: - the instrumental assembly; - the execution of an ACET test and the considerations relative to the samples and electrochemical cell, test parameters and procedure. ISO 17463:2014 also provides guidelines for the presentation of experimental results and other type of information obtained.

1 Scope This International Standard specifies the procedure for evaluation of the experimental set-up of electrochemical measurements on high-impedance coated samples using methods that are based on the current interrupter (CI) technique, relaxation voltammetry (RV) or DC transient (DCT) measurements. It provides specific definitions and guidance on optimizing the collection of CI, RV and DCT data from highimpedance systems. High impedance in the context of intact coatings refers to systems with an impedance greater than 109 Ω/cm2. This does not preclude measurements on systems with lower impedance. This International Standard deals in particular with: — instrumental set-up: requirements and shortcomings; — data validation: checking the measurement range and the accuracy of the data; — performing CI, RV, DCT measurements: specimen considerations and instrumental parameters; — the experimental results: different methods of presenting CI, RV and DCT data. Following the recommendations should ensure the acquisition of CI, RV and DCT data that can be used to study the performance of the specimen. This International Standard does not give guidelines for the interpretation of the data.

ISO 16773-3:2009 specifies a procedure for the evaluation of the experimental set-up used for carrying out EIS on high-impedance coated samples. For this purpose, dummy cells are used to simulate high-impedance coated samples. On the basis of the equivalent circuits described, ISO 16773-3 gives guidelines for the use of dummy cells to increase confidence in the test protocol, including making measurements, curve fitting and data presentation.

ISO 16773-4:2009 gives some typical examples of impedance spectra of high-impedance coated metal samples. Some guidance on interpretation of such spectra is also given.

ISO 16773-2:2007 provides guidance on optimizing the collection of EIS data from high-impedance systems. High impedance in the context of intact coatings refers to systems with an impedance greater than 109 ohm·cm2. This does not preclude measurements on systems with lower impedance. ISO 16773-2:2007 deals with instrumental set-up: requirements and pit-falls; data validation: checking the measurement range and the accuracy of the data; performing an EIS measurement: specimen considerations and instrumental parameters; the experimental results: different methods of presenting EIS data. It does not give guidelines for the interpretation of the data.

ISO 16773-1:2007 gives terms and definitions for electrochemical impedance spectroscopy (EIS) for use in the other parts of ISO 16773.