ASTM G28-02

Standard Test Methods of Detecting Susceptibility to Intergranular Corrosion in Wrought, Nickel-Rich, Chromium-Bearing Alloys

SCOPE
1.1 These test methods cover two tests as follows:
1.1.1 Method A, Ferric Sulfate-Sulfuric Acid Test (3-10 , inclusive)This test method describes the procedure for conducting the boiling ferric sulfate—50 % sulfuric acid test which measures the susceptibility of certain nickel-rich, chromium-bearing alloys to intergranular corrosion (see Terminology G 15), which may be encountered in certain service environments. The uniform corrosion rate obtained by this test method, which is a function of minor variations in alloy composition, may easily mask the intergranular corrosion components of the overall corrosion rate on alloys N10276, N06022, N06059, and N06455.
1.1.2 Method B, Mixed Acid-Oxidizing Salt Test (Sections 11-18, inclusive) This test method describes the procedure for conducting a boiling 23 % sulfuric + 1.2 % hydrochloric + 1 % ferric chloride + 1 % cupric chloride test which measures the susceptibility of certain nickel-rich, chromium-bearing alloys to display a step function increase in corrosion rate when there are high levels of grain boundary precipitation.
1.2 The purpose of these two test methods is to detect susceptibility to intergranular corrosion as influenced by variations in processing or composition, or both. Materials shown to be susceptible may or may not be intergranularly corroded in other environments. This must be established independently by specific tests or by service experience.
1.3 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. Hazard advisory statements are given in 5.1.1, 5.1.3, 5.1.9, 13.1.1, and 13.1.11.

General Information

• Status: Historical
• Publication Date: 09-Oct-2002
• ICS: 77.120.40 - Nickel, chromium and their alloys
• Technical Committee: G01 - Corrosion of Metals
• Drafting Committee: G01.05 - Laboratory Corrosion Tests

Relations

• Replaces: ASTM G28-97 - Standard Test Methods of Detecting Susceptibility to Intergranular Corrosion in Wrought, Nickel-Rich, Chromium-Bearing Alloys
• Effective Date: 10-Oct-2002
• Replaced By: ASTM G28-02(2008) - Standard Test Methods for Detecting Susceptibility to Intergranular Corrosion in Wrought, Nickel-Rich, Chromium-Bearing Alloys
• Effective Date: 01-May-2008
• Referred By: ASTM B1015-20 - Standard Practice for Form and Style of Standards Relating to Refined Nickel and Cobalt and Their Alloys
• Effective Date: 10-Oct-2002
• Referred By: ASTM B444-23 - Standard Specification for Nickel-Chromium-Molybdenum-Niobium Alloys<brk/> and Nickel-Chromium-Molybdenum-Silicon Alloy Pipe and Tube
• Effective Date: 10-Oct-2002
• Referred By: ASTM G31-21 - Standard Guide for Laboratory Immersion Corrosion Testing of Metals
• Effective Date: 10-Oct-2002
• Referred By: ASTM B834-22 - Standard Specification for Pressure Consolidated Powder Nickel Alloy Pipe Flanges, Fittings, Valves, and Parts
• Effective Date: 10-Oct-2002
• Referred By: 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
• Effective Date: 10-Oct-2002
• Referred By: ASTM G108-23 - Standard Test Methods for Electrochemical Reactivation (EPR) for Detecting Sensitization of AISI Type 304 and 304L Stainless Steels
• Effective Date: 10-Oct-2002

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:G28–02
Standard Test Methods of
Detecting Susceptibility to Intergranular Corrosion in
1
Wrought, Nickel-Rich, Chromium-Bearing Alloys
ThisstandardisissuedunderthefixeddesignationG 28;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscript
epsilon (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope 2. Referenced Document
1.1 These test methods cover two tests as follows: 2.1 ASTM Standards:
1.1.1 Method A, Ferric Sulfate-Sulfuric Acid Test (3-10 , A 262 Practices for Detecting Susceptibility to Intergranu-
2
inclusive)—This test method describes the procedure for lar Attack in Austenitic Stainless Steels
3
conducting the boiling ferric sulfate—50 % sulfuric acid test D 1193 Specification for Reagent Water
which measures the susceptibility of certain nickel-rich, G 15 Terminology Relating to Corrosion and Corrosion
4
chromium-bearing alloys to intergranular corrosion (see Ter- Testing
minology G 15), which may be encountered in certain service
METHOD A—Ferric Sulfate—Sulfuric Acid Test
environments. The uniform corrosion rate obtained by this test
method, which is a function of minor variations in alloy
3. Significance and Use
composition, may easily mask the intergranular corrosion
3.1 The boiling ferric sulfate-sulfuric acid test may be
components of the overall corrosion rate on alloys N10276,
applied to the following alloys in the wrought condition:
N06022, N06059, and N06455.
Alloy Testing Time, h
1.1.2 Method B, Mixed Acid-Oxidizing Salt Test (Sections
11-18, inclusive)—This test method describes the procedure
N06007 120
N06022 24
for conducting a boiling 23 % sulfuric + 1.2 % hydrochlo-
N06030 120
ric+1% ferric chloride+1% cupric chloride test which
N06059 24
measures the susceptibility of certain nickel-rich, chromium-
N06200 24
bearing alloys to display a step function increase in corrosion N06455 24
N06600 24
rate when there are high levels of grain boundary precipitation.
N06625 120
1.2 The purpose of these two test methods is to detect
N06686 24
N06985 120
susceptibility to intergranular corrosion as influenced by varia-
N08020 120
tions in processing or composition, or both. Materials shown to
N08367 24
be susceptible may or may not be intergranularly corroded in
N08800 120
A
N08825 120
other environments.This must be established independently by
N10276 24
specific tests or by service experience.
____________
1.3 This standard does not purport to address all of the
A
While the ferric sulfate-sulfuric acid test does detect susceptibility to inter-
safety concerns, if any, associated with its use. It is the
granular corrosion in Alloy N08825, the boiling 65 % nitric acid test, Practices
A 262, Practice C, for detecting susceptibility to intergranular corrosion in stainless
responsibility of the user of this standard to establish appro-
steels is more sensitive and should be used if the intended service is nitric acid.
priate safety and health practices and determine the applica-
3.2 This test method may be used to evaluate as-received
bility of regulatory limitations prior to use. Hazard advisory
material and to evaluate the effects of subsequent heat treat-
statements are given in 5.1.1, 5.1.3, 5.1.9, 13.1.1, and 13.1.11.
ments. In the case of nickel-rich, chromium-bearing alloys, the
test method may be applied to wrought and weldments of
products. The test method is not applicable to cast products.
1
These test methods are under the jurisdiction of ASTM Committee G01 on
Corrosion of Metals and are the direct responsibility of Subcommittee G01.05 on
2
Laboratory Corrosion Tests. Annual Book of ASTM Standards, Vol 01.03.
3
Current edition approved Oct. 10, 2002. Published January 2003. Originally Annual Book of ASTM Standards, Vol 11.01.
4
published as G 28 – 71. Last previous edition G 28 – 97. 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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G28–02
4. Apparatus
4.1 The apparatus (Note 1) is illustrated in Fig. 1.
FIG. 1 Apparatus for Ferric Sulfate-Sulfuric Acid Test
2

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G28–02
FIG. 2 Glass Cradle
5
4.1.1 Allihn or Soxhlet Condenser, 4-bulb, with a 45/50 4.1.2 Erlenmeyer Flask, 1-L, with a 45/50 ground-glass
ground-glass joint, overall length about 330 mm, condensing
joint. The ground-glass opening shall be 40 mm wide.
section about 240 mm.
4.1.3 Glass Cradle (Fig. 2)—To pass through the ground-
glass joint on the Erlenmeyer flask, the width of the
...