ASTM G78-01

Standard Guide for Crevice Corrosion Testing of Iron-Base and Nickel-Base Stainless Alloys in Seawater and Other Chloride-Containing Aqueous Environments

SCOPE
1.1 This guide provides information for conducting crevice-corrosion tests and identifies factors that may affect results and influence conclusions.  
1.2 These procedures can be used to identify conditions most likely to result in crevice corrosion and provide a basis for assessing the relative resistance of various alloys to crevice corrosion under certain specified conditions.  
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.4 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 and health practices and determine the applicability of regulatory limitations prior to use. For a specific precautionary statement, see 7.1.1.

General Information

• Status: Historical
• Publication Date: 09-May-2001
• ICS: 77.060 - Corrosion of metals
• Technical Committee: G01 - Corrosion of Metals

Relations

• Replaces: ASTM G78-95 - Standard Guide for Crevice Corrosion Testing of Iron-Base and Nickel-Base Stainless Alloys in Seawater and Other Chloride-Containing Aqueous Environments
• Effective Date: 10-May-2001
• Replaced By: ASTM G78-01(2007) - Standard Guide for Crevice Corrosion Testing of Iron-Base and Nickel-Base Stainless Alloys in Seawater and Other Chloride-Containing Aqueous Environments
• Effective Date: 01-May-2007
• Referred By: ASTM G1-03(2017)e1 - Standard Practice for Preparing, Cleaning, and Evaluating Corrosion Test Specimens
• Effective Date: 10-May-2001
• Referred By: ASTM G107-95(2020)e1 - Standard Guide for Formats for Collection and Compilation of Corrosion Data for Metals for Computerized Database Input
• Effective Date: 10-May-2001
• Referred By: ASTM G192-08(2020)e1 - Standard Test Method for Determining the Crevice Repassivation Potential of Corrosion-Resistant Alloys Using a Potentiodynamic-Galvanostatic-Potentiostatic Technique
• Effective Date: 10-May-2001
• Referred By: ASTM G52-20 - Standard Practice for Exposing and Evaluating Metals and Alloys in Surface Seawater
• Effective Date: 10-May-2001
• Referred By: ASTM G31-21 - Standard Guide for Laboratory Immersion Corrosion Testing of Metals
• Effective Date: 10-May-2001
• Referred By: ASTM G111-21a - Standard Guide for Corrosion Tests in High Temperature or High Pressure Environment, or Both
• Effective Date: 10-May-2001

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:G78–01
Standard Guide for
Crevice Corrosion Testing of Iron-Base and Nickel-Base
Stainless Alloys in Seawater and Other Chloride-Containing
1
Aqueous Environments
ThisstandardisissuedunderthefixeddesignationG78;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscript
epsilon (e) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
Crevice corrosion of iron-base and nickel-base stainless alloys can occur when an occlusion or
crevice limits access of the bulk environment to a localized area of the metal surface. Localized
environmental changes in this stagnant area can result in the formation of acidic/high chloride
conditions that may result in initiation and propagation of crevice corrosion of susceptible alloys.
In practice, crevices can generally be classified into two categories: (a) naturally occurring, that is,
those created by biofouling, sediment, debris, deposits, etc. and (b) man-made, that is, those created
during manufacturing, fabrication, assembly, or service. Crevice formers utilized in laboratory and
field studies can represent actual geometric conditions encountered in some service applications. Use
of such crevice formers in service-type environments are not considered accelerated test methods.
The geometry of a crevice can be described by the dimensions of crevice gap and crevice depth.
Crevice gap is identified as the width or space between the metal surface and the crevice former.
Crevice depth is the distance from the mouth to the center or base of the crevice.
2
1. Scope rosion Test Specimens
G4 Guide for Conducting Corrosion Coupon Tests in Field
1.1 Thisguideprovidesinformationforconductingcrevice-
2
Applications
corrosion tests and identifies factors that may affect results and
G15 Terminology Relating to Corrosion and Corrosion
influence conclusions.
2
Testing
1.2 These procedures can be used to identify conditions
G46 Guide for Examination and Evaluation of Pitting
mostlikelytoresultincrevicecorrosionandprovideabasisfor
2
Corrosion
assessing the relative resistance of various alloys to crevice
G48 Test Methods for Pitting and Crevice Corrosion Re-
corrosion under certain specified conditions.
sistance of Stainless Steels and Related Alloys by Use of
1.3 The values stated in SI units are to be regarded as the
2
Ferric Chloride Solution
standard. The values given in parentheses are for information
only.
3. Terminology
1.4 This standard does not purport to address all of the
3.1 Definitions of related terms can be found in Terminol-
safety concerns, if any, associated with its use. It is the
ogy G15.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
4. Significance and Use
bility of regulatory limitations prior to use. For a specific
4.1 This guide covers procedures for crevice-corrosion test-
precautionary statement, see 7.1.1.
ing of iron-base and nickel-base stainless alloys in seawater.
2. Referenced Documents The guidance provided may also be applicable to crevicecor-
rosion testing in other chloride containing natural waters and
2.1 ASTM Standards:
various laboratory prepared aqueous chloride environments.
G1 Practice for Preparing, Cleaning, and Evaluating Cor-
4.2 This guide describes the use of a variety of crevice
formers including the nonmetallic, segmented washer design
referred to as the multiple crevice assembly (MCA) as de-
1
This guide is under the jurisdiction ofASTM Committee G01 on Corrosion of
scribed in 9.2.2.
Metals and is the direct responsibility of Subcommittee G01.09 on Corrosion in
Natural Waters.
Current edition approved May 10, 2001. Published May 2001. Originally
2
published as G78–83. Last previous edition G78–95. Annual Book of ASTM Standards, Vol 03.02.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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G78–01
4.3 In-service performance data provide the most reliable each set of environmental, metallurgical, or geometric condi-
determination of whether a material would be satisfactory for tions to be evaluated. If reproducibility is unsatisfactory,
a particular end use. Translation of laboratory data from a additional specimens should be tested.
single test program to predict service performance under a
6.2 Dimensions of both the test specimen and crevice
variety of conditions should be avoided. Terms, such as
former should be determined and recorded.
immunity, superior resistance, etc., provide only a general and
6.3 Variations in the boldly exposed (crevice-free) to
relatively qualitative description of an alloy’s corrosion per-
sh
...