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5.1 The spiral contractometer, properly used, will give reproducible results (see 9.5) over a wide range of stress values. Internal stress limits with this method can be specified for use by both the purchaser and the producer of plated or electroformed parts.5.2 Plating with large tensile stresses will reduce the fatigue strength of a product made from high-strength steel. Maximum stress limits can be specified to minimize this. Other properties affected by stress include corrosion resistance, dimensional stability, cracking, and peeling.5.3 In control of electroforming solutions, the effects of stress are more widely recognized, and the control of stress is usually necessary to obtain a usable electroform. Internal stress limits can be determined and specified for production control.5.4 Internal stress values obtained by the spiral contractometer do not necessarily reflect the internal stress values found on a part plated in the same solution. Internal stress varies with many factors, such as coating thickness, preparation of substrate, current density, and temperature, as well as the solution composition. Closer correlation is achieved when the test conditions match those used to coat the part.1.1 This test method covers the use of the spiral contractometer for measuring the internal stress of metallic coatings as produced from plating solutions on a helical cathode. The test method can be used with electrolytic and autocatalytic deposits.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with 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.

定价: 590元 / 折扣价: 502 加购物车

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This specification establishes the requirements for brass and copper pipe nipples within a specified size range. Chromium-plated pipe nipples covered by this specification are intended for use in the interior of decorative appliances. Both brass and copper pipe nipples should be produced from regular or extra strong pipes while chromium-plated pipe nipples are produced from regular weight brass pipes. All pipe nipples should be threaded in both ends with NPT Taper Pipe Threads except for close nipples with lengths shorter than the specified value. Threads should be right hand on both ends except when otherwise specified. Chromium plated nipples use short plumbing (hospital) threads. Pipe nipple ends shall be cut reasonable square to the central axis and chamfered on the outside with all outside burrs removed.1.1 This specification establishes the requirements for brass and copper pipe nipples in standard pipe sizes from 1/8 to 8 in., inclusive, in standard lengths, and chromium-plated pipe nipples in standard pipe sizes from 1/8 to 2 in., inclusive, in standard lengths.1.1.1 Chromium-plated pipe nipples ordered under this specification are intended for interior use in decorative applications.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 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.

定价: 590元 / 折扣价: 502 加购物车

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This specification covers steel strip, nickel-clad or nickel-plated on both sides, for use in electron tubes. The base metal shall be an aluminum-deoxidized low-carbon steel conforming to the prescribed chemical composition requirements for iron, carbon, manganese, phosphorus, and sulfur, as determined by chemical analysis. The nickel plating shall conform to the prescribed chemical composition for nickel plus cobalt. The nickel cladding, Grade 1 (UNS N02233), Grade 2 (UNS N02202), and Grade 3 (UNS N02253), shall conform to the prescribed chemical composition for nickel (plus cobalt), carbon, copper, iron, magnesium, manganese, silicon, sulfur, and titanium. The requirements for the following are specified: (1) bonding of cladding or plating, (2) thickness of Type I and Type II cladding or plating which shall be determined by metallographic examination, (3) strip temper, and (4) strip mass and dimensions such as width, edgewise bow, edge, and burr. The surface shall be as smooth and free of dirt, oxide, pits, scratches, seams, slivers, streaks, stains, scale, blisters, edge cracks, trimming burrs, and other defects. Requirements for coiling and spoiling, product marking, and packaging are given as well.1.1 This specification covers steel strip, nickel-clad or nickel-plated on both sides, for use in electron tubes.1.2 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.

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5.1 This test method establishes a means to verify the prevention, to the extent possible, of IHE in steel fasteners during manufacture by maintaining strict controls during production operations such as surface preparation, pretreatments, and plating or coating. It is intended to be used as a qualification test for new or revised plating or coating processes and as a periodic inspection audit for the control of a plating or coating process.5.2 Passing this test allows fasteners to be stressed in tension to the minimum specified tensile load in air with almost no possibility of time delayed fracture in air as a result of IHE from processing. If the amount of residual hydrogen is not sufficient to induce cracking or fracture in the specimen under worst case conditions, then it can be concluded that all of the lots of fasteners processed during that period will not have sufficient residual hydrogen from processing to induce hydrogen embrittlement of the fasteners under stress in air if the process remains in control, unchanged and stable.5.3 If certified specimens with demonstrated sensitivity to IHE, processed with the fasteners, have a threshold ≥75 % of the incremental step load notched bend fracture stress, NFS(B)F1624, it is assumed that all fasteners processed the same way during the period will also pass any sustained load IHE test.FIG. 1 Dimensional Requirements for a 0.4W-Notched Square Bar Bend Specimen1.1 This test method covers a procedure to prevent, to the extent possible, internal hydrogen embrittlement (IHE) of fasteners by monitoring the plating or coating process, such as those described in Specifications F1137 and F1941. The process is quantitatively monitored on a periodic basis with a minimum number of specimens as compared to qualifying each lot of fasteners being plated or coated. Trend analysis is used to ensure quality as compared to statistical sampling analysis of each lot of fasteners. This test method consists of a mechanical test for the evaluation and control of the potential for IHE that may arise from various sources of hydrogen in a plating or coating process.1.2 This test method consists of a mechanical test, conducted on a standard specimen used as a witness, for the evaluation and control of the potential for IHE that may arise from various sources of hydrogen in a plating or coating process.1.3 This test method is limited to evaluating hydrogen induced embrittlement due only to processing (IHE) and not due to environmental exposure (EHE, see Test Method F1624).1.4 This test method is not intended to measure the relative susceptibility of steels to either IHE or EHE.1.5 This test method is limited to evaluating processes used for plating or coating ferrous fasteners.1.6 This test method uses a notched square bar specimen that conforms to Test Method F519, Type 1e, except that the radius is increased to accommodate the deposition of a larger range of platings and coatings. For the background on Test Method F519 testing, see publications ASTM STP 5432 and ASTM STP 962.3 The stress concentration factor is at a Kt = 3.1 ± 0.2. The sensitivity is demonstrated with a constant imposed cathodic potential to control the amount of hydrogen. Both the sensitivity and the baseline for residual hydrogen will be established with tests on bare metal specimens in air.1.7 The sensitivity of each lot of specimens to IHE shall be demonstrated. A specimen made of AISI E4340 steel heat treated to a hardness range of 50 to 52 HRC is used to produce a “worst case” condition and maximize sensitivity to IHE.1.8 The test is an accelerated (≤24 h) test method to measure the threshold for hydrogen stress cracking, and is used to quantify the amount of residual hydrogen in the specimen. The specimen undergoes sustained load and slow strain rate testing by using incremental loads and hold times under displacement control to measure a threshold stress in an accelerated manner in accordance with Test Method F1624.1.9 In this test method, bending is used instead of tension because it produces the maximum local limit load tensile stress in a notched bar of up to 2.3 times the yield strength as measured in accordance with Test Method E8/E8M. A fastener that is unintentionally exposed to bending on installation may attain this maximum local tensile stress.1.10 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.1.11 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.1.12 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.

定价: 590元 / 折扣价: 502 加购物车

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This specification covers carbonized nickel strip, carbonized nickel-plated, and nickel clad steel strips for use in electron tubes. The carbonized strips should have a uniform appearance with surfaces free of any lubricant. The firing process used for testing carbon loss should be done in a way that ensures an acceptable standard of quality for operation in electron-tube applications. Test specimens should be protected using a suitable covered boat to prevent radiation from the furnace heating elements or direct gas impingement. After firing, samples should not show any visual carbon loss or exposed uncarbonized bare metal. Unless otherwise specified, each coil or spool should be of continuous length of strip without any kind of joint. Each strip should be coiled so that the normal curvature is not reversed.1.1 This specification covers carbonized nickel strip and carbonized nickel-plated and nickel-clad steel strip for use in electron tubes.1.2 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.

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