ASTM E864-20

Standard Practice for Surface Preparation of Aluminum Alloys to Be Adhesively Bonded in Honeycomb Shelter Panels

SIGNIFICANCE AND USE
4.1 Durable adhesive bonds to aluminum alloys can be obtained reliably only through proper selection and careful control of the materials used and the steps in the bonding process. The preparation of the aluminum alloys to obtain clean, uniform surfaces with appropriate characteristics is a critical step. This practice describes how such surfaces can be obtained.
SCOPE
1.1 This practice covers the preparation of clean uniform surfaces of aluminum alloys suitable for formation of durable adhesive bonds to nonmetallic honeycomb materials in the manufacture of sandwich panels for tactical shelters.  
1.2 The values stated in SI units are to be regarded as standard where only SI units are given or where SI units are given first followed by inch-pound units; where inch-pound units are given first followed by SI units, the inch-pound units are to regarded as standard.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For a specific warning statement, see 6.2.1.  
1.4 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-Aug-2020
• ICS: 91.060.10 - Walls. Partitions. Facades
• ICS: 91.060.20 - Roofs
• Technical Committee: E06 - Performance of Buildings
• Drafting Committee: E06.53 - Materials and Processes for Durable Rigidwall Relocatable Structures

Relations

• Refers: ASTM E1749-18 - Standard Terminology Relating to Rigid Wall Relocatable Shelters
• Effective Date: 01-Oct-2018
• Refers: ASTM D3167-10(2017) - Standard Test Method for Floating Roller Peel Resistance of Adhesives
• Effective Date: 01-Nov-2017
• Refers: ASTM E631-15 - Standard Terminology of Building Constructions
• Effective Date: 01-Mar-2015
• Refers: ASTM E631-14 - Standard Terminology of Building Constructions
• Effective Date: 01-Nov-2014
• Refers: ASTM E866-11 - Standard Specification for Corrosion-Inhibiting Adhesive Primer for Aluminum Alloys to Be Adhesively Bonded in Honeycomb Shelter Panels
• Effective Date: 01-May-2011
• Refers: ASTM E1749-10 - Standard Terminology Relating to Rigid Wall Relocatable Shelters
• Effective Date: 01-Nov-2010
• Refers: ASTM D3167-10 - Standard Test Method for Floating Roller Peel Resistance of Adhesives
• Effective Date: 01-Oct-2010
• Refers: ASTM E865-08 - Standard Specification for Structural Film Adhesives for Honeycomb Sandwich Panels
• Effective Date: 01-Nov-2008
• Refers: ASTM E631-06 - Standard Terminology of Building Constructions
• Effective Date: 01-Jun-2006
• Refers: ASTM E1749-05 - Standard Terminology Relating to Rigid Wall Relocatable Shelters
• Effective Date: 01-Oct-2005
• Refers: ASTM E866-05 - Standard Specification for Corrosion-Inhibiting Adhesive Primer for Aluminum Alloys to Be Adhesively Bonded in Honeycomb Shelter Panels
• Effective Date: 01-May-2005
• Refers: ASTM D2674-72(2004)e1 - Standard Methods of Analysis of Sulfochromate Etch Solution Used in Surface Preparation of Aluminum
• Effective Date: 01-Apr-2004
• Refers: ASTM D3167-03a(2004) - Standard Test Method for Floating Roller Peel Resistance of Adhesives
• Effective Date: 01-Apr-2004
• Refers: ASTM D3167-03a - Standard Test Method for Floating Roller Peel Resistance of Adhesives
• Effective Date: 01-Oct-2003
• Refers: ASTM D3167-03 - Standard Test Method for Floating Roller Peel Resistance of Adhesives
• Effective Date: 10-May-2003

Overview

ASTM E864-20: Standard Practice for Surface Preparation of Aluminum Alloys to Be Adhesively Bonded in Honeycomb Shelter Panels is an internationally recognized guideline developed by ASTM International. This standard outlines the specific processes necessary to prepare the surfaces of aluminum alloys to ensure reliable and durable adhesive bonds during the manufacture of sandwich panels, especially for tactical and relocatable shelters.

Proper surface preparation is vital for optimal adhesive bonding. The process involves carefully selected materials and controlled procedures designed to produce clean, uniform surfaces with the appropriate characteristics needed for strong bonds between aluminum alloys and nonmetallic honeycomb materials.

Key Topics

• Purpose and Importance

  • Ensures durable adhesive bonds by providing detailed procedures for achieving clean, contamination-free aluminum surfaces.
  • Highlights the critical role of surface condition in successful bonding and long-term panel durability.

• Surface Preparation Methods

  • Stepwise procedures for cleaning, alkaline treatment, chemical etching, rinsing, and drying aluminum alloy components.
  • Detailed guidance for using either sulfo-chromate etch or sulfo-ferric etch processes.
  • Emphasis on the use of deionized or appropriately tested water at every stage to reduce the risk of contaminant-induced bonding failures.

• Equipment and Materials Control

  • Specifications for tanks, temperature controls, and material compatibility to avoid adverse reactions.
  • Recommendations for quality of chemicals, adhesives, and adherence to manufacturer guidelines.

• Quality Assurance

  • Requirement for routine process monitoring, visual inspections, and periodic peel strength testing to validate bonding integrity.
  • Comprehensive documentation, traceability, and record keeping for at least three years.

• Safety and Environmental Considerations

  • Users must establish appropriate procedures to address potential health, safety, and environmental risks, particularly concerning chemicals used in surface preparation.

Applications

ASTM E864-20 is primarily applied within industries involved in the fabrication of honeycomb sandwich panels for:

• Military and Tactical Shelters

  • Provides a foundation for constructing robust, lightweight, and relocatable shelters through reliable adhesive bonding of aluminum skins to nonmetallic cores.

• Portable and Rigidwall Shelter Systems

  • Ensures consistent, high-quality adhesion in panels used for deployable structures, supporting both defense and civilian emergency operations.

• Aerospace, Construction, and Transportation

  • Where sandwich panels with aluminum facings and honeycomb cores are specified, this standard helps maintain critical bond performance under demanding service conditions.

By following ASTM E864-20, manufacturers achieve reproducible bonding results, facilitating structural integrity, increased panel longevity, and compliance with end user and regulatory expectations.

Related Standards

ASTM E864-20 references and is complemented by several associated standards that collectively address material preparation, testing, and performance:

• ASTM D2674: Methods of Analysis of Sulfochromate Etch Solution Used in Surface Preparation of Aluminum
• ASTM D3167: Test Method for Floating Roller Peel Resistance of Adhesives
• ASTM E631: Terminology of Building Constructions
• ASTM E865: Specification for Structural Film Adhesives for Honeycomb Sandwich Panels
• ASTM E866: Specification for Corrosion-Inhibiting Adhesive Primer for Aluminum Alloys to Be Adhesively Bonded in Honeycomb Shelter Panels
• ASTM E1749: Terminology Relating to Rigid Wall Relocatable Shelters

These documents provide the necessary definitions, testing procedures, and additional requirements to ensure comprehensive quality control in the adhesive bonding of aluminum honeycomb panels.

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Keywords: surface preparation, aluminum alloys, adhesive bonding, honeycomb shelter panels, ASTM E864-20, sandwich panel manufacturing, relocatable shelters, bond durability

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: E864 − 20
Standard Practice for
Surface Preparation of Aluminum Alloys to Be Adhesively
Bonded in Honeycomb Shelter Panels
This standard is issued under the fixed designation E864; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope E865Specification for Structural Film Adhesives for Hon-
eycomb Sandwich Panels
1.1 This practice covers the preparation of clean uniform
E866 Specification for Corrosion-Inhibiting Adhesive
surfaces of aluminum alloys suitable for formation of durable
Primer forAluminumAlloys to BeAdhesively Bonded in
adhesive bonds to nonmetallic honeycomb materials in the
Honeycomb Shelter Panels
manufacture of sandwich panels for tactical shelters.
E1749Terminology Relating to Rigid Wall Relocatable
1.2 The values stated in SI units are to be regarded as
Shelters
standard where only SI units are given or where SI units are
2.2 APHA Standard:
given first followed by inch-pound units; where inch-pound
APHAStandard Methods for the Examination of Water and
units are given first followed by SI units, the inch-pound units
Waste Water (15th Edition, 1980), Sections 402, 403, and
are to regarded as standard.
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3. Terminology
responsibility of the user of this standard to establish appro-
3.1 Definitions—For definitions of general terms related to
priate safety, health, and environmental practices and deter-
building construction used in this practice, refer to Terminol-
mine the applicability of regulatory limitations prior to use.
ogy E631, and for general terms related to rigid wall relocat-
For a specific warning statement, see 6.2.1.
able shelters, refer to Terminology E1749.
1.4 This international standard was developed in accor-
dance with internationally recognized principles on standard-
4. Significance and Use
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
4.1 Durable adhesive bonds to aluminum alloys can be
mendations issued by the World Trade Organization Technical
obtained reliably only through proper selection and careful
Barriers to Trade (TBT) Committee.
control of the materials used and the steps in the bonding
process. The preparation of the aluminum alloys to obtain
2. Referenced Documents
clean, uniform surfaces with appropriate characteristics is a
critical step. This practice describes how such surfaces can be
2.1 ASTM Standards:
obtained.
D2674Methods ofAnalysis of Sulfochromate Etch Solution
Used in Surface Preparation of Aluminum
5. Apparatus
D3167Test Method for Floating Roller Peel Resistance of
Adhesives
5.1 General Processing:
E631Terminology of Building Constructions
5.1.1 All heated tanks shall be equipped with automatic
temperature controls and shall have means for agitation to
prevent local overheating of the solution. Solutions may be
heated by any internal or external means that do not change
This practice is under the jurisdiction of ASTM Committee E06 on Perfor-
mance of Buildings and is the direct responsibility of Subcommittee E06.53 on
their compositions. Steam shall not be introduced into any
Materials and Processes for Durable Rigidwall Relocatable Structures.
solution. Compressed air introduced into any solution or
Current edition approved Sept. 1, 2020. Published October 2020. Originally
equipment shall have been filtered to remove oil and moisture.
approved in 1982. Last previous edition approved in 2012 as E864–12. DOI:
10.1520/E0864-20.
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 Available from theAmerican Public HealthAssociation (APHA), 800 I Street,
the ASTM website. NW, Washington, DC 20001, http://www.apha.org.
Copyright ©ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA19428-2959. United States
E864 − 20
5.1.2 Tanksshallbemadefrom,orlinedwith,materialsthat 6.4 QualityAssuranceAdhesive—Theadhesivesystemused
havenoadverseeffectsonthesolutionsusedorthepartsbeing for the quality assurance tests of 9.6 shall meet Specification
treated. All tanks shall be of sufficient size to allow complete E865. The adhesive shall be changed only when a batch is
immersion of the largest part or assembly to be treated. almost exhausted so the results of any particular day’s testing
canbedirectlycomparedtotheresultsofprevioustests.When
5.2 Rinse Tanks—Immersion rinse tanks shall be equipped
a change is made in the batch or lot of adhesive used, an
with a means for skimming or overflowing or both to remove
additional set of tests shall be made to compare the old batch
surface contamination. The tanks shall be equipped with a
or lot with the new one to establish a basis for comparison
means for flushing hollow sections.
between the results obtained with each.
5.3 Rinses—Rinses, other than final rinses, shall be main-
tained in such a manner to prevent carryover of materials that
7. Test Methods
would adversely affect the next solution (for example, using a
7.1 Chemical Analyses—Perform chemical analyses of the
fog water rinse as the aluminum part/assembly is being
water and solutions as indicated in 7.2 and 7.3. Analyze as
withdrawn from the rinse tank).
often as necessary to maintain the required concentrations at a
minimum of every day of operation. If a process is not in use
6. Materials
during the normal analysis period, note this on the analysis
6.1 Water—Water used for makeup of processing solutions
record and analyze the solution prior to further use.
and final rinsing shall be deionized water or shall meet the
7.2 Water Analyses—Analyze as described in APHA Stan-
requirementofTable1.Analysesshallbeperformedasoftenas
dard Methods for the Examination of Water and Waste Water.
necessary to assure that the water meets the requirements.
Samples for analysis shall be collected at the processing tanks. 7.3 Etch Solution Analysis:
7.3.1 Sulfo-Chromate Etch—Perform the analyses in accor-
6.2 Etch Solution:
dance with Methods D2674.
6.2.1 Method I, Sulfo-Chromate Etch (FPL)—The chemical
7.3.2 Sulfo-Ferric Etch—Perform the analyses in accor-
analysis of the etch solution shall be maintained at approxi-
dance with 7.3.2.1 and 7.3.2.2.
mately 30 parts by mass of water, ten parts by mass of sulfuric
7.3.2.1 Sulfuric Acid—Pipeta1mL(0.03 oz) sample into a
acid (sp gr 1.84), and one to four parts by mass of sodium
250 mL (8.5 oz) Erlenmeyer flask containing 100 mL (3.4 oz)
dichromate. Prior to use, a minimum of 0.06 part by mass of
of distilled water. Add 1 g (0.03 oz) of tribasic sodium citrate
dissolved 2024 aluminum shall be added. (Warning—It is
and 1 g (0.03 oz) of sodium fluoride. Add 2 to 3 drops of
recognized that chromates present a hazard to health. Use and
phenolphthaleinindicator.Titratewith0.4Nsodiumhydroxide
disposal procedures are governed by Federal and Local EPA
toclearorfaintpink.Calculatethenormalityofsulfuricacidin
and DER limitations.)
accordance with Table 2.
6.2.2 Method II, Sulfo-Ferric Etch (P )—The chemical
7.3.2.2 Ferric Ion—Pipeta2mL (0.06 oz) sample into a
analysis of the etch solution shall be maintained at approxi-
250 mL (8.5 oz) Erlenmeyer flask containing 100 mL (3.4 oz)
mately 27 to 36% by weight of sulfuric acid (sp gr 1.84) and
of distilled water. Add 10 mL (0.3 oz) of concentrated
2.9 to 4.7 oz/gal of ferric iron or 18 to 22 oz/gal of ferric
hydrochloric acid. Add 1 g to 2 g (0.03 oz to 0.06 oz) of
sulfate. This is the equivalent of 2 gal of concentrated sulfuric
potassium iodide titrate with 0.10 N sodium thiosulfate to a
acid and 12.5 lb of ferric sulfate in every 10 gal of solution.
greenish color. Add about 2 mL of starch solution. Continue
Two gallons of a 50% ferric sulfate solution may be used in
titration to a clear green end point. Calculate ferric sulfate as
place of the 12.5 lb of the powdered ferric sulfate.
follows:
NOTE1—Onlyvirginferricsulfatesolutionshallbeusedinthisprocess.
Impurities in reclaimed ferric sulfate will cause unwanted reactions when
mLsodiumthiosulfateused 32.79 5 g/L ferricion (1)
the aluminum is treated.
7.4 Visual Inspection—Inspect parts visually for stains and
6.3 Alkaline Cleaning Solution—Nonetch, alkaline cleaning
water break.
solution shall be prepared in accordance with the manufactur-
er’s recommendations, or as indicated in 8.1.2. When the
aluminumbeingcleanedisimmersedinthealkalinecleanerfor
TABLE 2 Calculation of Normality of Sulfuric Acid to Percent by
the time and at the temperature used for processing, there shall
Weight (1 g/100 g)
benoevidenceofgasevolution
...

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: E864 − 12 E864 − 20
Standard Practice for
Surface Preparation of Aluminum Alloys to Be Adhesively
Bonded in Honeycomb Shelter Panels
This standard is issued under the fixed designation E864; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope
1.1 This practice covers the preparation of clean uniform surfaces of aluminum alloys suitable for formation of durable adhesive
bonds to nonmetallic honeycomb materials in the manufacture of sandwich panels for tactical shelters.
1.2 The values stated in SI units are to be regarded as the standard where only SI units are given or where SI units are given first
followed by inch-pound units; where inch-pound units are given first followed by SI units, the inch-pound units are to regarded
as the standard.
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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use. For a specific warning statement, see 6.2.1.
1.4 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
2.1 ASTM Standards:
D2674 Methods of Analysis of Sulfochromate Etch Solution Used in Surface Preparation of Aluminum
D3167 Test Method for Floating Roller Peel Resistance of Adhesives
E631 Terminology of Building Constructions
E865 Specification for Structural Film Adhesives for Honeycomb Sandwich Panels
E866 Specification for Corrosion-Inhibiting Adhesive Primer for Aluminum Alloys to Be Adhesively Bonded in Honeycomb
Shelter Panels
E1749 Terminology Relating to Rigid Wall Relocatable Shelters
2.2 APHA Standard:
APHA Standard Methods for the Examination of Water and Waste Water (15th Edition, 1980), Sections 402, 403, and 408
3. Terminology
3.1 Definitions—See Terminologies —For definitions of general terms related to building construction used in this practice, refer
This practice is under the jurisdiction of ASTM Committee E06 on Performance of Buildings and is the direct responsibility of Subcommittee E06.53 on Materials and
Processes for Durable Rigidwall Relocatable Structures.
Current edition approved Nov. 1, 2012Sept. 1, 2020. Published December 2012October 2020. Originally approved in 1982. Last previous edition approved in 20082012
as E864 – 08.E864 – 12. DOI: 10.1520/E0864-12.10.1520/E0864-20.
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’sstandard’s Document Summary page on the ASTM website.
Available from the American Public Health Association (APHA), 800 I Street, NW, Washington, DC 20001-3710,20001, http://www.apha.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E864 − 20
to Terminology E631, and E1749 for definitions of general terms used in this practice.for general terms related to rigid wall
relocatable shelters, refer to Terminology E1749.
4. Significance and Use
4.1 Durable adhesive bonds to aluminum alloys can be obtained reliably only through proper selection and careful control of the
materials used and the steps in the bonding process. The preparation of the aluminum alloys to obtain clean, uniform surfaces with
appropriate characteristics is a critical step. This practice describes how such surfaces can be obtained.
5. Apparatus
5.1 General Processing:
5.1.1 All heated tanks shall be equipped with automatic temperature controls and shall have means for agitation to prevent local
overheating of the solution. Solutions may be heated by any internal or external means that do not change their compositions.
Steam shall not be introduced into any solution. Compressed air introduced into any solution or equipment shall have been filtered
to remove oil and moisture.
5.1.2 Tanks shall be made from, or lined with, materials that have no adverse effects on the solutions used or the parts being
treated. All tanks shall be of sufficient size to allow complete immersion of the largest part or assembly to be treated.
5.2 Rinse Tanks—Immersion rinse tanks shall be equipped with a means for skimming or overflowing or both to remove surface
contamination. The tanks shall be equipped with a means for flushing hollow sections.
5.3 Rinses—Rinses, other than final rinses, shall be maintained in such a manner to prevent carryover of materials that would
adversely affect the next solution (for example, using a fog water rinse as the aluminum part/assembly is being withdrawn from
the rinse tank).
6. Materials
6.1 Water—Water used for makeup of processing solutions and final rinsing shall be deionized water or shall meet the requirement
of Table 1. Analyses shall be performed as often as necessary to assure that the water meets the requirements. Samples for analysis
shall be collected at the processing tanks.
6.2 Etch Solution:
6.2.1 Method I, Sulfo-Chromate Etch (FPL)—The chemical analysis of the etch solution shall be maintained at approximately 30
parts by mass of water, ten parts by mass of sulfuric acid (sp gr 1.84), and one to four parts by mass of sodium dichromate. Prior
to use, a minimum of 0.06 part by mass of dissolved 2024 aluminum shall be added. (Warning—It is recognized that chromates
present a hazard to health. Use and disposal procedures are governed by Federal and Local EPA and DER limitations.)
6.2.2 Method II, Sulfo-Ferric Etch (P )—The chemical analysis of the etch solution shall be maintained at approximately 27 to
36 % by weight of sulfuric acid (sp gr 1.84) and 2.9 to 4.7 oz/gal of ferric iron or 18 to 22 oz/gal of ferric sulfate. This is the
equivalent of 2 gal of concentrated sulfuric acid and 12.5 lb of ferric sulfate in every 10 gal of solution. Two gallons of a 50 %
ferric sulfate solution may be used in place of the 12.5 lb of the powdered ferric sulfate.
NOTE 1—Only virgin ferric sulfate solution shall be used in this process. Impurities in reclaimed ferric sulfate will cause unwanted reactions when the
aluminum is treated.
TABLE 1 Requirements for Water to Be Used in Solutions and
Rinses
Requirements
Min Max
pH 6.0 8.0
Total solids, ppm . 200
Total alkalinity as CaCO , ppm . 125
Chloride content, ppm . 15
E864 − 20
6.3 Alkaline Cleaning Solution—Nonetch, alkaline cleaning solution shall be prepared in accordance with the
manufacturer’smanufacturer’s recommendations, or as indicated in 8.1.2. When the aluminum being cleaned is immersed in the
alkaline cleaner for the time and at the temperature used for processing, there shall be no evidence of gas evolution, etching, or
metal removal. The alkaline solution shall not contain silicates.
6.4 Quality Assurance Adhesive—The adhesive system used for the quality assurance tests of 9.6 shall meet Specification E865.
The adhesive shall be changed only when a batch is almost exhausted so the results of any particular day’s testing can be directly
compared to the results of previous tests. When a change is made in the batch or lot of adhesive used, an additional set of tests
shall be made to compare the old batch or lot with the new one to establish a basis for comparison between the results obtained
with each.
7. Test Methods
7.1 Chemical Analyses—Perform chemical analyses of the water and solutions as indicated in 7.2 and 7.3. Analyze as often as
necessary to maintain the required concentrations at a minimum of every day of operation. If a process is not in use during the
normal analysis period, note this on the analysis record and analyze the solution prior to further use.
7.2 Water Analyses—Analyze as described in APHA Standard Methods for the Examination of Water and Waste Water.
7.3 Etch Solution Analysis:
7.3.1 Sulfo-Chromate Etch—Perform the analyses in accordance with Methods D2674.
7.3.2 Sulfo-Ferric Etch—Perform the analyses in accordance with 7.3.2.1 and 7.3.2.2.
7.3.2.1 Sulfuric Acid—Pipet a 1-mL (0.03-oz) 1 mL (0.03 oz) sample into a 250-mL (8.5-oz) 250 mL (8.5 oz) Erlenmeyer flask
containing 100 mL (3.4 oz) of distilled water. Add 1 g (0.03 oz) of tribasic sodium citrate and 1 g (0.03 oz) of sodium fluoride.
Add 2 to 3 drops of phenolphthalein indicator. Titrate with 0.4 N sodium hydroxide to clear or faint pink. Calculate the normality
of sulfuric acid in accordance with Table 2.
7.3.2.2 Ferric Ion—Pipet a 2-mL (0.06-oz) 2 mL (0.06 oz) sample into a 250-mL (8.5-oz) 250 mL (8.5 oz) Erlenmeyer flask
containing 100 mL (3.4 oz) of distilled water. Add 10 mL (0.3 oz) of concentrated hydrochloric acid. Add 1 g to 2 g (0.03 oz to
0.06 oz) of potassium iodide titrate with 0.10 N sodium thiosulfate to a greenish color. Add about 2 mL of starch solution. Continue
titration to a clear green end point. Calculate ferric sulfate as follows:
mL sodium thiosulfate used 32.79 5 g/L ferric ion (1)
7.4 Visual Inspection—Inspect parts visually for stains and water break.
7.5 Floating Roller Peel Test—Test in accordance with Test Method D3167.
TABLE 2 Calculation of Normality of Sulfuric Acid to Percent by
Weight (1 g/100 g)
NOTE 1—N sulfuric acid = mL 0.4 N NaOH × 0.4
N % N %
4.65 = 20 7.76 = 31
4.91 = 21 8.06 =
...