1.1 该试验方法确定了重复剪切力对夹芯板中使用的芯材的影响。允许的芯材形式包括具有连续粘合表面的芯材（如轻木和泡沫）以及具有不连续粘合表面（如蜂窝）的芯材。 1.2 该试验方法仅限于承受恒定振幅单轴载荷的试样，其中控制机器以使试样承受重复的恒定振幅力（应力）循环。剪切应力或施加的力可以用作恒定振幅疲劳变量。 1.3 以国际单位制或英寸磅单位表示的数值应单独视为标准。 每个系统中规定的值不一定是完全相等的；因此，为了确保符合标准，每个系统应独立使用，并且不得将两个系统的值组合使用。在文本中，英寸磅单位显示在括号中。 1.4 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.5 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 通常，夹芯板芯所承受的最临界应力是剪切应力。重复剪切应力对芯材的影响可能非常重要，特别是在各种环境条件下的耐久性方面。 5.2 该试验方法提供了获得夹层芯剪切疲劳响应的标准方法。用途包括筛选特定应用的候选堆芯材料，制定特定设计的堆芯剪切循环应力极限，以及堆芯材料的研究和开发。 注3: 此测试方法可作为进行频谱加载的指南。这些信息有助于理解谱载荷条件下堆芯的疲劳行为，但本标准未涵盖这些信息。 5.3 影响堆芯疲劳响应的因素包括:堆芯材料、堆芯几何形状（密度、单元尺寸、方向等）、试样几何形状和相关测量精度、试样制备、试样调节、试验环境、试样对准、加载程序、加载频率、力（应力）比和试验速度（用于残余强度试验）。 注4: 如果使用本标准的指导对夹层板进行测试，则以下内容也可能影响疲劳响应，应予以报告:饰面材料、粘合剂材料、材料制造方法、粘合剂厚度和粘合剂空隙率。 此外，在具有相同芯材和饰面材料的夹层板中，预固化/粘结和共固化饰面之间的芯材-饰面强度可能不同。

1.1 This test method determines the effect of repeated shear forces on core material used in sandwich panels. Permissible core material forms include those with continuous bonding surfaces (such as balsa wood and foams) as well as those with discontinuous bonding surfaces (such as honeycomb). 1.2 This test method is limited to test specimens subjected to constant amplitude uniaxial loading, where the machine is controlled so that the test specimen is subjected to repetitive constant amplitude force (stress) cycles. Either shear stress or applied force may be used as a constant amplitude fatigue variable. 1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined. Within the text, the inch-pound units are shown in brackets. 1.4 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. 1.5 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 Often the most critical stress to which a sandwich panel core is subjected is shear. The effect of repeated shear stresses on the core material can be very important, particularly in terms of durability under various environmental conditions. 5.2 This test method provides a standard method of obtaining the sandwich core shear fatigue response. Uses include screening candidate core materials for a specific application, developing a design-specific core shear cyclic stress limit, and core material research and development. Note 3: This test method may be used as a guide to conduct spectrum loading. This information can be useful in the understanding of fatigue behavior of core under spectrum loading conditions, but is not covered in this standard. 5.3 Factors that influence core fatigue response and shall therefore be reported include the following: core material, core geometry (density, cell size, orientation, etc.), specimen geometry and associated measurement accuracy, specimen preparation, specimen conditioning, environment of testing, specimen alignment, loading procedure, loading frequency, force (stress) ratio and speed of testing (for residual strength tests). Note 4: If a sandwich panel is tested using the guidance of this standard, the following may also influence the fatigue response and should be reported: facing material, adhesive material, methods of material fabrication, adhesive thickness and adhesive void content. Further, core-to-facing strength may be different between precured/bonded and co-cured facings in sandwich panels with the same core and facing materials.