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This practice can be used for detection of hexavalent chromium on galvanized and zinc/aluminum alloy coated steel surfaces. Hexavalent chromium-bearing treatments (passivates) can be applied to coated steels to prevent storage stain. Chrome passivation may interfere with the successful pretreatment of galvanized steel, as well as contaminate cleaning and pretreatment baths on a coil coating line. This practice is designed to be a qualitative means of screening chrome passivated coils from those which are not chrome passivated. The following materials will be required to perform the stripping procedure: (1) dark colored or brown polyethylene wash bottle, or brown glass dropper bottle, and (2) test specimens which may be cut panels or coil stock. The following chemical reagents are required to perform this procedure: 1,5-diphenylcarbohydrazide, acetone, ethanol, phosphoric acid, and distilled water. The preparation of indicator solution, procedure of detection, and evaluation of pink color development are detailed. If a material that yields a negative result is suspected of having chromium on the surface, instrumental methods should be used. This technique is not recommended for acrylic resin containing passivation treatments.1.1 This practice can be used to detect the presence of hexavalent chromium on galvanized and zinc/aluminum alloy coated steel surfaces. Hexavalent chromium-bearing treatments (passivates) can be applied to coated steels to prevent storage stain. While passivated 55 % aluminum-zinc alloy coated steel is commonly painted, passivated galvanized steel is not. Chrome passivation may interfere with the successful pretreatment of galvanized steel, as well as contaminate cleaning and pretreatment baths on a coil coating line.1.2 The amount of hexavalent chromium that will cause the indicator to produce a discernible pink color is in the range of 0.5 parts per million dissolved in the indicator solution. It is possible that a coated steel surface that produces a negative result does have chromium on the surface. If a material that yields a negative result is suspected of having chromium on the surface, instrumental methods should be used. Chrome deposits of 1 mg/ft2 can be easily missed by analytical instruments such as the scanning electron microscope with energy dispersive x-ray analysis (EDXA) capability. Auger electron spectroscopy (AES) or electron spectroscopy for chemical analysis (ESCA) can identify chemical species present in the levels required for adequate detection. Stripping the metallic coating and analyzing for chrome by atomic absorption or inductively coupled plasma can also give reliable results in detecting the presence of chrome.1.3 This practice is designed to be a qualitative means of screening chrome passivated coils from those which are not chrome passivated.1.4 Some chromium-free passivates are being used commercially. Although these products will test negative for hexavalent chromium, they may interfere with cleaning and pretreating. Chromium bearing passivates that contain film forming constituents such as acrylic resins are also being commercially applied. The reaction of these products to the spot test will vary. Abrading the surface with emery paper will improve the likelihood of reliable detection. This technique is not recommended for acrylic resin containing passivation treatments.1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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.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.

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4.1 The formation of reproducible, durable-adhesive bonds in structural units requires great care in the selection of materials, the preparation of the surfaces of the parts to be bonded, and the performance of the steps in the bonding process. Experience has shown that adhesive bonding carried out in accordance with this practice produces relatively reproducible bonds.1.1 This practice describes the materials, processes, and quality controls to be used in the manufacture of adhesive-bonded, aluminum-faced, nonmetallic-honeycomb-core sandwich panels for tactical shelters.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 This standard does not purport to address 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.

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4.1 Reproducible and 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.1.1 This practice covers the preparation of clean, uniform surfaces of aluminum alloy suitable for formation of durable adhesive bonds in “foam and beam” panels used for the manufacture of tactical rigid wall shelters.1.2 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.1.3 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.

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5.1 Refer to Guide E844 for the selection, irradiation, and quality control of neutron dosimeters.5.2 Refer to Practice E261 for a general discussion of the determination of fast-neutron fluence rate with threshold detectors.5.3 Pure aluminum in the form of foil or wire is readily available and easily handled. 27Al has an abundance of 100 % (1).35.4 24Na has a half-life of 14.958 (2)4 h (2) and emits gamma rays with energies of 1.368630 (5) and 2.754049 (13) MeV (2).5.5 Fig. 1 shows a plot of the International Reactor Dosimetry and Fusion File (IRDFF-II) cross section (3, 4) versus neutron energy for the fast-neutron reaction 27Al(n,α) 24Na (3) along with a comparison to the current experimental database (5, 6). While the RRDF-2008 and IRDFF-1.05 cross sections extend from threshold up to 60 MeV, due to considerations of the available validation data, the energy region over which this standard recommends use of this cross section for reactor dosimetry applications only extends from threshold at ~4.25 MeV up to 20 MeV. This figure is for illustrative purposes and is used to indicate the range of response of the 27Al(n,α) reaction. Refer to Guide E1018 for recommended sources for the tabulated dosimetry cross sections.FIG. 1 27Al(n,α)24Na Cross Section, from IRDFF-II Library, with EXFOR Experimental Data5.6 Two competing activities, 28Al (2.25 (2) minute half-life) and 27Mg (9.458 (12) minute half-life), are formed in the reactions 27Al(n,γ)28Al and 27Al(n,p)27Mg, respectively, but these can be eliminated by waiting 2 h before counting.1.1 This test method covers procedures measuring reaction rates by the activation reaction 27Al(n,α)24Na.1.2 This activation reaction is useful for measuring neutrons with energies above approximately 6.5 MeV and for irradiation times up to about two days (for longer irradiations, or when there are significant variations in reactor power during the irradiation, see Practice E261).1.3 With suitable techniques, fission-neutron fluence rates above 106 cm−2·s−1 can be determined.1.4 Detailed procedures for other fast neutron detectors are referenced in Practice E261.1.5 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.1.6 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.

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This specification covers the basic physical requirements for steel chain-link fence fabric that are aluminum-coated before weaving. Fabrics conforming to this specification shall meet specified requirements for weave form and typical diamond count, size of mesh, size of wire, height of fabric, selvage, weight of aluminum coating, breaking strength, workmanship and finish, and standard length of rolls.1.1 This specification covers aluminum-coated steel chain-link fence fabric, aluminum-coated before weaving.1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.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.

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This specification covers the manufacturing and testing requirements for copper clad aluminum rectangular bar for electrical (bus) applications. Six classes of copper-clad aluminum bar are covered:1.1 This specification covers copper clad aluminum rectangular bar for electrical (bus) applications.1.2 Six classes of copper-clad aluminum bar are covered as follows:Class 20A—Nominal 20 volume % copper, annealed.Class 25A—Nominal 25 volume % copper, annealed.Class 30A—Nominal 30 volume % copper, annealed.Class 20H—Nominal 20 volume % copper, hard-worked.Class 25H—Nominal 25 volume % copper, hard-worked.Class 30H—Nominal 30 volume % copper, hard-worked.1.3 The values stated in inch-pound units are to be regarded as the standard, except for resistivity and density, where the SI units are the standard. The values given in parentheses are for information only.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.

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4.1 The Webster hardness gage is portable and therefore useful for in situ determination of the hardness of fabricated parts and individual test specimens for production control purposes. It is not as sensitive as Rockwell or Brinell hardness machines; see 10.2.4.2 This test method should be used only as cited in applicable material specifications.1.1 This test method covers the determination of indentation hardness of aluminum alloys with a Webster hardness gage, Model B.1.2 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.NOTE 1: Two other models, A and B-75, are in use, but are not covered in this test method. Model A does not provide numerical values of hardness and Model B-75 covers only a part of the range of interest for aluminum alloys.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.

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