1.1 本试验方法涵盖了通过监测镀层或涂层过程（如规范中所述）来尽可能防止紧固件内部氢脆（IHE）的程序 F1137 和 1941年 与对每批电镀或涂层的紧固件进行资格鉴定相比，该过程定期进行定量监测，并使用最少数量的试样。与每批紧固件的统计抽样分析相比，趋势分析用于确保质量。该测试方法包括机械测试，用于评估和控制镀覆或涂层过程中各种氢源可能引起的IHE的可能性。 1.2 该试验方法包括对用作见证的标准试样进行机械试验，以评估和控制镀层或涂层过程中各种氢源可能引起的IHE的可能性。 1.3 本试验方法仅限于评估仅因加工（IHE）而非环境暴露（EHE）引起的氢致脆化，见试验方法 F1624 ). 1.4 本试验方法不用于测量钢对IHE或EHE的相对敏感性。 1.5 本试验方法仅限于评估用于镀或涂覆铁紧固件的工艺。 1.6 本试验方法使用符合试验方法的带缺口方杆试样 F519 1e型，除了半径增加以适应更大范围的镀层和涂层的沉积。关于测试方法的背景 F519 测试，见出版物ASTM STP 543 2. 以及ASTM STP 962。 3. 应力集中系数为 K t = 3.1 ± 0.2. 通过施加恒定的阴极电势来控制氢气的量，可以证明这种灵敏度。残余氢的灵敏度和基线将通过在空气中对裸金属试样进行测试来确定。 1.7 应证明每批试样对IHE的敏感性。使用由AISI E4340钢制成的试样进行热处理，硬度范围为50至52 HRC，以产生“最坏情况”条件，并最大限度地提高对IHE的敏感性。 1.8 测试是加速的( ≤ 24小时）测量氢应力开裂阈值的试验方法，用于量化试样中残留的氢量。根据试验方法，通过在位移控制下使用增量载荷和保持时间，对试样进行持续载荷和慢应变率测试，以加速方式测量阈值应力 F1624 . 1.9 在该试验方法中，使用弯曲代替拉伸，因为它在缺口钢筋中产生的最大局部极限载荷拉应力高达根据试验方法测量的屈服强度的2.3倍 E8/E8M 在安装过程中无意中暴露在弯曲中的紧固件可能会达到这种最大的局部拉应力。 1.10 以英寸-磅单位表示的值应被视为标准值。括号中给出的值是对国际单位制的数学转换，仅供参考，不被视为标准值。 1.11 本标准并不旨在解决与其使用相关的所有安全问题（如果有的话）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践，并确定监管限制的适用性。 1.12 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 =====意义和用途====== 5.1 本试验方法建立了一种方法，通过在表面处理、预处理和镀层或涂层等生产操作中保持严格控制，在制造过程中尽可能地验证钢紧固件中IHE的预防。它旨在用作新的或修订的镀层或涂层工艺的资格测试，以及镀层或涂层过程控制的定期检查审核。 5.2 通过该测试，紧固件可以在空气中承受最小规定的拉伸载荷，几乎不可能因加工过程中的IHE而在空气中发生延时断裂。如果残余氢的量不足以在最坏的情况下导致试样开裂或断裂，那么可以得出结论，如果工艺保持可控、不变和稳定，那么在此期间加工的所有紧固件批次都不会有足够的残余氢来诱导紧固件在空气应力下的氢脆。 5.3 如果用紧固件处理的对IHE敏感的认证试样具有阈值 ≥ 75%的增量阶跃载荷缺口弯曲断裂应力NFS（B） F1624 ，假设在此期间以相同方式加工的所有紧固件也将通过任何持续载荷IHE测试。

1.1 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 543 2 and ASTM STP 962. 3 The stress concentration factor is at a K t = 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. ====== Significance And Use ====== 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.