ASTM G35-23

Standard Practice for Determining the Susceptibility of Stainless Steels and Related Nickel-Chromium-Iron Alloys to Stress-Corrosion Cracking in Polythionic Acids

SIGNIFICANCE AND USE
4.1 Polythionic acids are chemically described as H2SxO6, where x is usually 3, 4, or 5 (1)3 though can be more than 50 (2). These acid environments provide a way of evaluating the resistance of stainless steels and related alloys to intergranular stress corrosion cracking. Failure is accelerated by the presence of increasing amounts of intergranular precipitate. Results for the polythionic acid test have not been correlated exactly with those of intergranular corrosion tests (Test Methods G28). Also, this test may not be relevant to stress corrosion cracking in chlorides or caustic environments.  
4.2 The polythionic acid environment may produce areas of shallow intergranular attack in addition to the more localized and deeper cracking mode of attack. Examination of failed specimens is necessary to confirm that failure occurred by cracking rather than mechanical failure of reduced sections.
SCOPE
1.1 This practice covers procedures for preparing and conducting the polythionic acid test at room temperature, 22 °C to 25 °C (72 °F to 77 °F), to determine the relative susceptibility of stainless steels or other related materials (nickel-chromium-iron alloys) to intergranular stress corrosion cracking.  
1.2 This practice can be used to evaluate stainless steels or other materials in the “as received” condition or after being subjected to high-temperature service, 482 °C to 815 °C (900 °F to 1500 °F), for prolonged periods of time.  
1.3 This practice can be applied to wrought products, castings, and weld metal of stainless steels or other related materials to be used in environments containing sulfur or sulfides. Other materials capable of being sensitized can also be tested in accordance with this test.  
1.4 This practice may be used with a variety of stress corrosion test specimens, surface finishes, and methods of applying stress.  
1.5 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.  
1.6 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. For more specific precautionary statements, see Section 7.  
1.7 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-May-2023
• ICS: 77.040.10 - Mechanical testing of metals
• ICS: 77.060 - Corrosion of metals
• Technical Committee: G01 - Corrosion of Metals
• Drafting Committee: G01.06 - Environmentally Assisted Cracking

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: G35 − 23
Standard Practice for
Determining the Susceptibility of Stainless Steels and
Related Nickel-Chromium-Iron Alloys to Stress-Corrosion
1
Cracking in Polythionic Acids
This standard is issued under the fixed designation G35; 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 practice covers procedures for preparing and con- 2.1 ASTM Standards:
ducting the polythionic acid test at room temperature, 22 °C to D1193 Specification for Reagent Water
25 °C (72 °F to 77 °F), to determine the relative susceptibility G1 Practice for Preparing, Cleaning, and Evaluating Corro-
of stainless steels or other related materials (nickel-chromium- sion Test Specimens
iron alloys) to intergranular stress corrosion cracking. G28 Test Methods for Detecting Susceptibility to Inter-
granular Corrosion in Wrought, Nickel-Rich, Chromium-
1.2 This practice can be used to evaluate stainless steels or
Bearing Alloys
other materials in the “as received” condition or after being
G30 Practice for Making and Using U-Bend Stress-
subjected to high-temperature service, 482 °C to 815 °C
Corrosion Test Specimens
(900 °F to 1500 °F), for prolonged periods of time.
G193 Terminology and Acronyms Relating to Corrosion
1.3 This practice can be applied to wrought products,
castings, and weld metal of stainless steels or other related
3. Summary of Practice
materials to be used in environments containing sulfur or
3.1 Stressed test specimens are placed in the container along
sulfides. Other materials capable of being sensitized can also
with a sensitized and stressed AISI Type 302 (UNS S30200) or
be tested in accordance with this test.
Type 304 (UNS S30400) stainless steel control specimen. A
1.4 This practice may be used with a variety of stress
sufficient amount of prepared polythionic acid solution is
corrosion test specimens, surface finishes, and methods of
added to the container to immerse the test specimens. A cover
applying stress.
is placed on the container and the test exposure is carried out
at room temperature followed by inspection for cracks.
1.5 The values stated in SI units are to be regarded as
standard. The values given in parentheses after SI units are
4. Significance and Use
provided for information only and are not considered standard.
4.1 Polythionic acids are chemically described as H S O ,
2 x 6
1.6 This standard does not purport to address all of the
3
where x is usually 3, 4, or 5 (1) though can be more than 50
safety concerns, if any, associated with its use. It is the
(2). These acid environments provide a way of evaluating the
responsibility of the user of this standard to establish appro-
resistance of stainless steels and related alloys to intergranular
priate safety, health, and environmental practices and deter-
stress corrosion cracking. Failure is accelerated by the presence
mine the applicability of regulatory limitations prior to use.
of increasing amounts of intergranular precipitate. Results for
For more specific precautionary statements, see Section 7.
the polythionic acid test have not been correlated exactly with
1.7 This international standard was developed in accor-
those of intergranular corrosion tests (Test Methods G28).
dance with internationally recognized principles on standard-
Also, this test may not be relevant to stress corrosion cracking
ization established in the Decision on Principles for the
in chlorides or caustic environments.
Development of International Standards, Guides and Recom-
4.2 The polythionic acid environment may produce areas of
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee. shallow intergranular attack in addition to the more localized
1 2
This practice is under the jurisdiction of ASTM Committee G01 on Corrosion For referenced ASTM standards, visit the ASTM website, www.astm.org, or
of Metals and is the direct responsibility of Subcommittee G01.06 on Environmen- contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
tally Assisted Cracking. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved June 1, 2023. Published June 2023. Originally the ASTM website.
3
approved in 1988. Last previous edition approved in 2015 as G35 – 98 (2015). DOI: The boldface numbers in parentheses refer to a list of references at the end of
10.1520/G0035-23. this stand
...

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: G35 − 98 (Reapproved 2015) G35 − 23
Standard Practice for
Determining the Susceptibility of Stainless Steels and
Related Nickel-Chromium-Iron Alloys to Stress-Corrosion
1
Cracking in Polythionic Acids
This standard is issued under the fixed designation G35; 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 practice covers procedures for preparing and conducting the polythionic acid test at room temperature, 22 to 25°C (72
to 77°F),22 °C to 25 °C (72 °F to 77 °F), to determine the relative susceptibility of stainless steels or other related materials
(nickel-chromiumiron(nickel-chromium-iron alloys) to intergranular stress corrosion cracking.
1.2 This practice can be used to evaluate stainless steels or other materials in the “as received” condition or after being subjected
to high-temperature service, 482 to 815°C (900 to 1500°F),482 °C to 815 °C (900 °F to 1500 °F), for prolonged periods of time.
1.3 This practice can be applied to wrought products, castings, and weld metal of stainless steels or other related materials to be
used in environments containing sulfur or sulfides. Other materials capable of being sensitized can also be tested in accordance
with this test.
1.4 This practice may be used with a variety of stress corrosion test specimens, surface finishes, and methods of applying stress.
1.5 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.
1.6 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 healthsafety, health, and environmental practices and determine
the applicability of regulatory limitations prior to use. For more specific precautionary statements, see Section 7.
1.7 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:
D1193 Specification for Reagent Water
G1 Practice for Preparing, Cleaning, and Evaluating Corrosion Test Specimens
1
This practice is under the jurisdiction of ASTM Committee G01 on Corrosion of Metals and is the direct responsibility of Subcommittee G01.06 on Environmentally
Assisted Cracking.
Current edition approved Nov. 1, 2015June 1, 2023. Published November 2015June 2023. Originally approved in 1988. Last previous edition approved in 20102015 as
G35–98(2010).G35 – 98 (2015). DOI: 10.1520/G0035-98R15.10.1520/G0035-23.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
G35 − 23
G15G28 Terminology Relating to Corrosion and Corrosion TestingTest Methods for Detecting Susceptibility to Intergranular
Corrosion in Wrought, Nickel-Rich, Chromium-Bearing Alloys (Withdrawn 2010)
G30 Practice for Making and Using U-Bend Stress-Corrosion Test Specimens
G193 Terminology and Acronyms Relating to Corrosion
3. Summary of Practice
3.1 The stressedStressed test specimens are placed in the container along with a sensitized and stressed AISI Type 302 (UNS
S30200) or Type 304 (UNS S30400) stainless steel control specimen. A sufficient amount of the previously prepared polythionic
acid solution is added to the container to immerse the test specimens. A cover is placed on the container and the test exposure is
carried out at room temperature.temperature followed by inspection for cracks.
4. Significance and Use
3
4.1 This environment provides Polythionic acids are chemically described as H S O , where x is usually 3, 4, or 5 (1) though
2 x 6
can be more than 50 (2). These acid environments provide a way of evaluating the resistance of stainless steels
...