ASTM E1794-22a

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of the standard as published by ASTM is to be considered the official document.
Designation: E1794 − 22 E1794 − 22a
Standard Specification for
Adhesive for Bonding Foam Cored Sandwich Panels (200 °F
Elevated Humidity Service), Type II Panels
This standard is issued under the fixed designation E1794; 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 specification covers two-part adhesives for bonding foam core sandwich panels. The adhesive may be used for new
production or depot maintenance. The adhesive should be suitable for forming bonds that can withstand long-term exposure to
temperatures from −55 °C to 93 °C (−67 °F to 200 °F) and also withstand combinations of stress, temperature, and humidity
expected to be encountered in service. The adhesives shall be used for bonding aluminum alloy facing to foam core, inserts,
internal aluminum framing members, and other components of a foam cored sandwich panel.
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 be 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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
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:
B209 Specification for Aluminum and Aluminum-Alloy Sheet and Plate (Metric) B0209_B0209M
D1002 Test Method for Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Tension Loading
(Metal-to-Metal)
E631 Terminology of Building Constructions
E864 Practice for Surface Preparation of Aluminum Alloys to Be Adhesively Bonded in Honeycomb Shelter Panels
E1749 Terminology Relating to Rigid Wall Relocatable Shelters
E1801 Practice for Adhesive Bonding of Aluminum Facings in Foam and Beam Type Shelters
2.2 Military Standard:
MIL-STD-202-101 Method 101, Salt Atmosphere (Corrosion)
This specification 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 March 15, 2022May 1, 2022. Published March 2022May 2022. Originally approved in 1996. Last previous edition approved in 20212022 as
E1794 – 21a.E1794 – 22. DOI: 10.1520/E1794-22.10.1520/E1794-22A.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
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E1794 − 22a
2.3 SAE Specification:
AMS-QQ-A-250 Aluminum and Aluminum Alloy, Plate and Sheet General Specification for
3. Terminology
3.1 Definitions:
3.1.1 For definitions of general terms related to building construction used in this specification, refer to Terminology E631, and
for general terms related to rigid wall relocatable shelters, refer to Terminology E1749.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 adhesive life, n—the maximum time that an adhesive, when mixed in a prescribed quantity can set at a designated
temperature, after which the adhesive, when used to prepare specimens, will deliver the required properties.
4. Requirements
4.1 Material—The adhesive shall be a two-part thermosetting epoxy paste containing no asbestos and, when tested using the test
methods described in Section 6, shall meet the requirements of Section 4. The adhesive shall not have a deleterious effect on the
components being bonded over the range of temperatures at which the adhesive will be used.
4.2 Working Characteristics:
4.2.1 Application—The adhesive shall be suitable for application to facings and foam core materials. The adhesive shall be suitable
for spray application to faying surfaces.
4.2.2 Curing—The time, temperature, and pressure used to cure the adhesive shall be within the range specified herein.
4.2.2.1 Curing Time and Temperature—The adhesive, when mixed in accordance with the manufacturer’s instructions, shall meet
the requirements of this specification when cured at a temperature of not more than 99 °C (210 °F) for 60 min, or 107 °C (225 °F)
for 45 min. The timing of the cure shall start when the panel skins have reached the specified temperature. The temperature for
the cure shall be fully attained within 3 h after the first application of the adhesive to the faying surface.
4.2.2.2 Curing Pressure—Specimens for testing under this specification shall be cured under a normal load of 50 kPa 6 14 kPa
(8.0 psi 6 1.0 psi). No more than 2 h at 25 °C (77 °F) shall elapse between the application of the adhesive to the faying surface
and the application of the pressure.
4.2.3 Mix Ratio—The mix ratio for the two parts of the adhesive shall be as defined by the manufacturer.
4.3 Storage Life—The storage life shall not exceed one year from the date of manufacture, when the components of the adhesive
are stored at a temperature between 10 °C (50 °F) and 42 °C (90 °F). The adhesive shall be considered to have met this storage
life requirement if all the characteristics described in 4.1 and 4.5 are met by the adhesive after the one year storage period described
above.
4.4 Adhesive Working Life—The adhesive life of one quartworking life is defined as the time period after mixing during which
the adhesive will produce acceptable bonds following the guidelines of ASTM E1801 of the process practice for a Type II shelter
panel. The adhesive working life of the properly prepared mixed adhesive at 25 °C (77 °F) shall not be less than 120 min (2 h),
at which time the adhesive be a minimum of 120 min. Verification shall be determined by preparing lap shear coupons with
adhesive that has been mixed and allowed to sit for 120 min before applying 8 psi bonding pressure and attaining maximum cure
temperature not less than 3 h following adhesive mixing. Coupons prepared by this method shall meet the requirements of 4.5.
4.5 Mechanical Properties—The minimum mechanical properties of the adhesives, when cured as specified, shall meet the
requirements of Table 1.
Available from SAE International (SAE), 400 Commonwealth Dr., Warrendale, PA 15096, http://www.sae.org.
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