ASTM G31-21

Standard Guide for Laboratory Immersion Corrosion Testing of Metals

SIGNIFICANCE AND USE
4.1 Corrosion testing by its very nature precludes complete standardization. This standard, rather than a standardized procedure, is presented as a guide so that some of the pitfalls of such testing may be avoided.  
4.2 Experience has shown that all metals and alloys do not respond alike to the many factors that affect corrosion and that accelerated corrosion tests give indicative results only, or may even be entirely misleading. It is impractical to propose an inflexible standard laboratory corrosion testing procedure for general use, except for material qualification tests where standardization is required. One purpose for this guide is to promote better correlation of results in the future and the reduction of conflicting reports through a more detailed recording of meaningful factors and conditions.  
4.3 In designing any corrosion test, consideration should be given to the various factors discussed in this guide, because these factors have been found to affect the results obtained.
SCOPE
1.1 This guide covers and describes the factors that influence laboratory immersion corrosion tests, particularly mass loss tests. These factors include apparatus, sampling, test specimen, test conditions (test solution composition, temperature, gas sparging, fluid motion, solution volume, method of supporting test specimens, duration of test), methods of cleaning test specimens, interpretation of results, and calculation of corrosion rates. This guide also emphasizes the importance of recording all pertinent data and provides a checklist for reporting test data.  
1.2 The specific evaluation of localized attack, environmentally assisted cracking, and effects of solution flow are not within the scope of this guide.  
1.3 This guide is intended to be used by those designing laboratory immersion tests who may not be familiar with all of the variables to consider and the pitfalls that could be encountered when designing and conducting this kind of testing. It should be used as a reference to ensure that the test will allow generation of data relevant to the application with the minimum of interferences.  
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Dec-2020
• ICS: 77.060 - Corrosion of metals
• Technical Committee: J01 - Joint ASTM/NACE Committee on Corrosion
• Drafting Committee: J01.01 - Working Group on Laboratory Immersion Tests

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: NACE TM0169/G31 − 21
Standard Guide for
1
Laboratory Immersion Corrosion Testing of Metals
This standard is issued under the fixed designation NACE TM0169/G31; the number immediately following the designation indicates
the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
2
1.1 This guide covers and describes the factors that influ- 2.1 ASTM Standards:
ence laboratory immersion corrosion tests, particularly mass A262 Practices for Detecting Susceptibility to Intergranular
loss tests. These factors include apparatus, sampling, test Attack in Austenitic Stainless Steels
specimen, test conditions (test solution composition, D1193 Specification for Reagent Water
temperature, gas sparging, fluid motion, solution volume, E8/E8M Test Methods for Tension Testing of Metallic Ma-
methodofsupportingtestspecimens,durationoftest),methods terials
of cleaning test specimens, interpretation of results, and E300 Practice for Sampling Industrial Chemicals
calculation of corrosion rates. This guide also emphasizes the G1 Practice for Preparing, Cleaning, and Evaluating Corro-
importance of recording all pertinent data and provides a sion Test Specimens
checklist for reporting test data. G28 Test Methods for Detecting Susceptibility to Inter-
granular Corrosion in Wrought, Nickel-Rich, Chromium-
1.2 The specific evaluation of localized attack, environmen-
Bearing Alloys
tally assisted cracking, and effects of solution flow are not
G34 Test Method for Exfoliation Corrosion Susceptibility in
within the scope of this guide.
2XXX and 7XXX Series Aluminum Alloys (EXCO Test)
1.3 This guide is intended to be used by those designing
G46 Guide for Examination and Evaluation of Pitting Cor-
laboratory immersion tests who may not be familiar with all of
rosion
the variables to consider and the pitfalls that could be encoun-
G48 Test Methods for Pitting and Crevice Corrosion Resis-
tered when designing and conducting this kind of testing. It
tance of Stainless Steels and Related Alloys by Use of
should be used as a reference to ensure that the test will allow
Ferric Chloride Solution
generation of data relevant to the application with the mini-
G66 Test Method for Visual Assessment of Exfoliation
mum of interferences.
Corrosion Susceptibility of 5XXX Series Aluminum Al-
loys (ASSET Test)
1.4 The values stated in SI units are to be regarded as
standard. The values given in parentheses after SI units are G67 Test Method for Determining the Susceptibility to
Intergranular Corrosion of 5XXX Series Aluminum Al-
provided for information only and are not considered standard.
loysbyMassLossAfterExposuretoNitricAcid(NAMLT
1.5 This standard does not purport to address all of the
Test)
safety concerns, if any, associated with its use. It is the
G71 Guide for Conducting and Evaluating Galvanic Corro-
responsibility of the user of this standard to establish appro-
sion Tests in Electrolytes
priate safety, health, and environmental practices and deter-
G78 Guide for Crevice Corrosion Testing of Iron-Base and
mine the applicability of regulatory limitations prior to use.
Nickel-Base Stainless Alloys in Seawater and Other
1.6 This international standard was developed in accor-
Chloride-Containing Aqueous Environments
dance with internationally recognized principles on standard-
G82 Guide for Development and Use of a Galvanic Series
ization established in the Decision on Principles for the
for Predicting Galvanic Corrosion Performance
Development of International Standards, Guides and Recom-
G107 Guide for Formats for Collection and Compilation of
mendations issued by the World Trade Organization Technical
Corrosion Data for Metals for Computerized Database
Barriers to Trade (TBT) Committee.
Input
1
This guide is under the jurisdiction of NACE/ASTM Committee J01, Joint
Committee on Corrosion, and is the direct responsibility of Subcommittee J01.01,
2
Working Group on Laboratory Immersion Tests. For referenced ASTM standards, visit the ASTM Web site, www.astm.org, or
Current edition approved Jan. 1, 2021. Published February 2021. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1972. Last previous ASTM edition approved in 2012 as G31–12a. Standards volume information, refer to the standard’s Document Summary page on
NACE edition originally approved in 1969. Last previous NACE edition approved theASTMWeb site. For NACE standards, visit the NACEWeb site, www.nace.org,
in
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: NACE TM0169/G31 − 12a
NACE TM0169/G31 − 21
Standard Guide for
1
Laboratory Immersion Corrosion Testing of Metals
This standard is issued under the fixed designation NACE TM0169/G31; the number immediately following the designation indicates
the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This guide covers and describes the factors that influence laboratory immersion corrosion tests, particularly mass loss tests.
These factors include apparatus, sampling, test specimen, test conditions (test solution composition, temperature, gas sparging,
fluid motion, solution volume, method of supporting test specimens, duration of test), methods of cleaning test specimens,
interpretation of results, and calculation of corrosion rates. This guide also emphasizes the importance of recording all pertinent
data and provides a checklist for reporting test data.
1.2 The specific evaluation of localized attack, environmentally assisted cracking, and effects of solution flow are not within the
scope of this guide.
1.3 This guide is intended to be used by those designing laboratory immersion tests who may not be familiar with all of the
variables to consider and the pitfalls that could be encountered when designing and conducting this kind of testing. It should be
used as a reference to ensure that the test will allow generation of data relevant to the application with the minimum of
interferences.
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.after
SI units are provided for information only and are not considered standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2
2.1 ASTM Standards:
A262 Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels
D1193 Specification for Reagent Water
1
This guide is under the jurisdiction of NACE/ASTM Committee J01, Joint Committee on Corrosion, and is the direct responsibility of Subcommittee J01.01, Working
Group on Laboratory Immersion Tests.
Current edition approved July 1, 2012Jan. 1, 2021. Published October 2012February 2021. Originally approved in 1972. Last previous ASTM edition approved in 2012
as G31–12.–12a. NACE edition originally approved in 1969. Last previous NACE edition approved in 20002012 as TM0169-2000.TM0169-2012. DOI: 10.1520/G0031-12A.
10.1520/G0031-21.
2
For referenced ASTM standards, visit the ASTM Web site, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’sstandard’s Document Summary page on the ASTM Web site. For NACE standards, visit the NACE Web site, www.nace.org, or
contact NACE First Service at fi[e-mail].
© NACE International/ASTM International 2021 – All rights reserved
1

---------------------- Page: 1 ----------------------
NACE TM0169/G31 − 21
E8E8/E8M Test Methods for Tension Testing of Metallic Materials [Metric] E0008_E0008M
E300 Practice for Sampling Industrial Chemicals
G1 Practice for Preparing, Cleaning, and Evaluating Corrosion Test Specimens
G28 Test Methods for Detecting Susceptibility to Intergranular Corrosion in Wrought, Nickel-Rich, Chromium-Bearing Alloys
G34 Test Method for Exfoliation Corrosion Susceptibility in 2XXX and 7XXX Series Aluminum Alloys (EXCO Test)
G46 Guide for Examination and Evaluation of Pitting Corrosion
G48 Test Methods for Pitting and Crevice Corrosion Resistance of Stainless Steels and Related Alloys by Use of Ferric Chloride
Solution
G66 Test Method for Visual Assessment of Exfoliation Corrosion Susceptibility of 5XXX Series Aluminum Alloys (ASSET
Test)
G67 Test Method for Determining the Susceptibility to Intergranular Corrosion of 5XXX Series Al
...