1.1 本规程涵盖了一种使用夹层长梁弯曲试样对由高模量纤维增强的薄损伤多向聚合物基复合材料层压板进行压缩测试的方法。它提供了一种测试配置，其中核心不会限制任何突出的后侧损伤。它仅限于测试单片固体层压板，这些层压板太薄，无法使用典型的防屈曲夹具进行测试。它不包括受损夹芯板面板的压缩试验。复合材料形式仅限于连续纤维或不连续纤维（带或织物，或两者兼而有之）增强复合材料，其中层压板相对于测试方向是平衡对称的 1.2 以国际单位制或英寸-磅单位表示的值应单独视为标准值。 每个系统中所述的值不一定是完全等效的；因此，为确保符合标准，每个系统应独立使用，两个系统的值不得组合。 1.2.1 在文本中，英寸-磅单位显示在括号中。 1.3 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。 1.4 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 本规程提供了一种测试受损复合材料层压板的标准方法，这些层压板太薄，无法使用典型的防屈曲夹具进行测试，如测试方法中使用的夹具 D7137/D7137M 首先冲击或压痕层压板，以产生代表实际单片固体层压板结构的损伤状态。在组装好的夹芯板上不进行冲击或静态压痕，因为在冲击或压痕事件中，芯部的能量吸收和芯部的支撑会改变损伤状态。损坏后，将层压板粘合到芯上，使层压板的受冲击或压痕侧紧贴芯，并使局部未粘合区域包围损坏部位。 图1 图示了去除粘合剂以避免损坏区域，以及将夹层试样与受冲击的受损层压板从冲击或压痕方向翻转的组装。然后使用长梁弯曲装置对最终组装的夹层试样进行测试，受损层压板位于压缩侧。夹层板配置被用作薄受损层压板的防屈曲支撑形式。 5.2 对平面外集中力的损伤敏感性是许多由先进复合材料层压板制成的结构的主要设计问题之一。了解层压复合板的抗损伤性和损伤容限性能对于产品开发和材料选择非常有用。 5.3 使用该试验方法获得的残余强度数据用于研发活动以及设计容许值； 然而，这些结果是特定于所测试的几何形状和物理条件的，通常无法扩展到其他配置。 5.4 使用这种测试方法获得的性能可以为类似材料、厚度、堆叠顺序等的复合材料结构的预期损伤容限能力提供指导。然而，必须理解的是，复合材料结构的损伤容限在很大程度上取决于几个因素，包括几何形状、刚度、支撑条件等。由于这些参数的差异，现有损伤状态和残余抗压强度之间的关系可能会出现显著差异。例如，使用这种测试方法获得的残余强度和刚度特性更有可能反映非金属材料的损伤容限特性- 与附着在子结构上的抵抗平面外变形的蒙皮相比，加固的整体蒙皮或腹板。 5.5 报告部分要求报告可能影响残余抗压强度的项目；这些包括以下内容:材料、材料制造方法、铺层方向的准确性、层压板堆叠顺序和总厚度、试样几何形状、试样制备、试样调节、测试环境、孔隙含量、体积百分比增强、损伤类型、尺寸和位置（包括无损检测（NDI）方法）、夹具几何形状、温度时间和测试速度。 5.6 残余强度评估得出的特性包括:抗压残余强度F 蔡 .

1.1 This practice covers an approach for compressive testing thin damaged multidirectional polymer matrix composite laminates reinforced by high-modulus fibers using a sandwich long beam flexure specimen. It provides a test configuration in which the core does not constrain any protruding back side damage. It is limited to testing of monolithic solid laminates which are too thin to be tested using typical anti-buckling fixtures. It does not cover compressive testing of damaged sandwich panel facings. The composite material forms are limited to continuous-fiber or discontinuous-fiber (tape or fabric, or both) reinforced composites in which the laminate is balanced and symmetric with respect to the test direction 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 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. 1.2.1 Within the text the inch-pound units are shown in brackets. 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. ====== Significance And Use ====== 5.1 This practice provides a standard method of testing damaged composite laminates which are too thin to be tested using typical anti-buckling fixtures, such as those used in Test Method D7137/D7137M . The laminate is first impacted or indented in order to produce a damage state representative of actual monolithic solid laminate structure. Impacting or static indentation is not performed on an assembled sandwich panel, as the damage state is altered by energy absorption in the core and by support of the core during the impact or indentation event. After damaging, the laminate is bonded onto the core with the impacted or indentation side of the laminate against the core, and with a localized un-bonded area encompassing the damage site. Fig. 1 illustrates the adhesive removal to avoid the damaged area and the assembly of the sandwich specimen with the impacted damaged laminate flipped over from the impacting or indentation orientation. The final assembled sandwich specimen is then tested using a long beam flexure setup with the damaged laminate being on the compression side. The sandwich panel configuration is used as a form of anti-buckling support for the thin damaged laminate. 5.2 Susceptibility to damage from concentrated out-of-plane forces is one of the major design concerns of many structures made of advanced composite laminates. Knowledge of the damage resistance and damage tolerance properties of a laminated composite plate is useful for product development and material selection. 5.3 The residual strength data obtained using this test method is used in research and development activities as well as for design allowables; however the results are specific to the geometry and physical conditions tested and are generally not scalable to other configurations. 5.4 The properties obtained using this test method can provide guidance in regard to the anticipated damage tolerance capability of composite structures of similar material, thickness, stacking sequence, and so forth. However, it must be understood that the damage tolerance of a composite structure is highly dependent upon several factors including geometry, stiffness, support conditions, and so forth. Significant differences in the relationships between the existent damage state and the residual compressive strength can result due to differences in these parameters. For example, residual strength and stiffness properties obtained using this test method would more likely reflect the damage tolerance characteristics of an un-stiffened monolithic skin or web than that of a skin attached to substructure which resists out-of-plane deformation. 5.5 The reporting section requires items that tend to influence residual compressive strength to be reported; these include the following: material, methods of material fabrication, accuracy of lay-up orientation, laminate stacking sequence and overall thickness, specimen geometry, specimen preparation, specimen conditioning, environment of testing, void content, volume percent reinforcement, type, size and location of damage (including method of non-destructive inspection (NDI)), fixture geometry, time at temperature, and speed of testing. 5.6 Properties that result from the residual strength assessment include the following: compressive residual strength F CAI .