1.1 本试验方法测定了受到集中压痕力的多向聚合物基复合材料层压板的抗损伤性( 图1 ). 规定了用于确定支撑在圆形开口上的试样和刚性支撑试样的抗损伤性的程序。复合材料形式仅限于连续纤维增强聚合物基复合材料，可接受的测试层压板和厚度范围见 8.2 该试验方法可能对其他类型和类别的复合材料有用。 图1 准静态压痕试验 1.1.1 实践中提供了修改这些程序以确定夹层结构抗损伤性能的说明 D7766/D7766米 . 1.2 通过将半球形压头缓慢压入表面，使扁平的方形复合板受到平面外的集中力。损伤阻力是根据临界接触力来量化的，以在试样中造成特定尺寸和类型的损伤。 1.3 该测试方法可用于筛选材料的抗损伤性，或对试样造成损伤，以进行后续的损伤容限测试。 随后可根据试验方法对压痕板进行试验 D7137/D7137米 以测量残余强度特性。每个试验方法的跌落重量冲击 D7136/D7136米 可以用作从平面外力产生损伤和测量抗损伤性能的替代方法。 1.4 该试验方法产生的抗损伤性能在很大程度上取决于几个因素，包括试样几何形状、叠层、压头几何形状、力和边界条件。因此，结果通常不能扩展到其他配置，并且对于测试的几何和物理条件的组合是特定的。 1.5 单位- 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精确的等效值；因此，为了确保符合标准，每个系统应独立使用，并且两个系统的值不应合并。 1.5.1 在文本中，英寸磅单位显示在括号中。 1.6 本标准并非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。 1.7 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 平面外集中力对损伤的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。层压复合材料板的抗损伤性能知识对产品开发和材料选择很有用。 5.2 QSI测试可以达到以下目的: 5.2.1 模拟受边界条件控制的碰撞的力-位移关系 ( 1- 7. ) . 5. 这些通常是相对较大质量的低速硬体对具有相对较小无支撑区域的板的冲击。由于测试在位移控制中缓慢进行，因此可以以可控的方式获得所需的损伤状态。由于力历史中的振荡，在落锤冲击试验过程中，将特定损伤事件与力联系起来通常很困难。此外，在准地震期间可能会识别出一系列特定的损伤事件- 静态载荷，而最终损伤状态只有在跌落重量冲击试验后才能识别。 5.2.2 如果所有其他参数保持不变，则为落锤冲击试验提供获得类似损伤状态所需的冲击能量估计。 5.2.3 定量确定堆叠顺序、纤维表面处理、纤维体积分数变化以及加工和环境变量对特定复合材料层压板对集中压痕力的抗损伤性的影响。 5.2.4 定量比较不同成分复合材料的抗损伤参数的相对值。 损伤响应参数可以包括凹陷深度、损伤尺寸和贯穿厚度位置， F 最大值 , E 一 和 E 最大值 ，以及力与压头位移的关系曲线。 5.2.5 为随后的损伤容限测试（如测试方法）赋予试样损伤 D7137/D7137米 . 5.2.6 使用两种试样配置（边缘支撑和刚性支撑）测量有弯曲和无弯曲试样的压痕响应。 5.3 使用该测试方法获得的性能可以为类似材料、厚度、堆叠顺序等复合材料结构的预期抗损伤能力提供指导。 然而，必须理解的是，复合材料结构的抗损伤性在很大程度上取决于几个因素，包括几何形状、厚度、刚度、质量、支撑条件等。由于这些参数的差异，可能会导致力/能量与最终损伤状态之间的关系出现显著差异。例如，使用支撑在圆孔上的试样获得的性能更有可能反映未加筋的整体蒙皮或腹板的抗损伤特性，而不是连接到子结构上的蒙皮的抗损伤特征- 抵抗平面外变形的结构。类似地，与比试样大得多的面板的性能相比，试样的性能预计与具有等效长度和宽度尺寸的面板的特性相似，这往往会将更大比例的能量转移到弹性变形中。 5.4 标准压头的几何形状为钝的半球形尖端。从历史上看，对于标准层压板配置，这种压头几何形状在给定的外部损伤量下产生的内部损伤量比使用尖锐尖端的类似压头通常观察到的更大。 根据所检查的抗损伤特性，替代压头几何形状可能是合适的。例如，尖锐尖端几何形状的使用可能适用于某些损伤可见性和穿透阻力评估。 5.5 一些测试机构可能希望将此测试方法与测试方法结合使用 D7137/D7137米 以评估包含特定损伤状态的试样的压缩残余强度，例如定义的凹痕深度、损伤几何形状等。在这种情况下，测试机构应使用该测试方法对几个试样进行多个能量或力水平的测试。 然后可以建立能量或力与期望的损伤参数之间的关系。随后的QSI和压缩残余强度测试可以使用在插值能量或力水平下缩进的试样进行，该插值能量或作用力水平预计会产生所需的损伤状态。

1.1 This test method determines the damage resistance of multidirectional polymer matrix composite laminated plates subjected to a concentrated indentation force ( Fig. 1 ). Procedures are specified for determining the damage resistance for a test specimen supported over a circular opening and for a rigidly-backed test specimen. The composite material forms are limited to continuous-fiber reinforced polymer matrix composites, with the range of acceptable test laminates and thicknesses defined in 8.2 . This test method may prove useful for other types and classes of composite materials. FIG. 1 Quasi-Static Indentation Test 1.1.1 Instructions for modifying these procedures to determine damage resistance properties of sandwich constructions are provided in Practice D7766/D7766M . 1.2 A flat, square composite plate is subjected to an out-of-plane, concentrated force by slowly pressing a hemispherical indenter into the surface. The damage resistance is quantified in terms of a critical contact force to cause a specific size and type of damage in the specimen. 1.3 The test method may be used to screen materials for damage resistance, or to inflict damage into a specimen for subsequent damage tolerance testing. The indented plate can be subsequently tested in accordance with Test Method D7137/D7137M to measure residual strength properties. Drop-weight impact per Test Method D7136/D7136M may be used as an alternate method of creating damage from an out-of-plane force and measuring damage resistance properties. 1.4 The damage resistance properties generated by this test method are highly dependent upon several factors, which include specimen geometry, layup, indenter geometry, force, and boundary conditions. Thus, results are generally not scalable to other configurations, and are particular to the combination of geometric and physical conditions tested. 1.5 Units— 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. 1.5.1 Within the text the inch-pound units are shown in brackets. 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. ====== Significance And Use ====== 5.1 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 properties of a laminated composite plate is useful for product development and material selection. 5.2 QSI testing can serve the following purposes: 5.2.1 To simulate the force-displacement relationships of impacts governed by boundary conditions ( 1- 7 ) . 5 These are typically relatively large-mass low-velocity hard-body impacts on plates with a relatively small unsupported region. Since the test is run slowly in displacement control, the desired damage state can be obtained in a controlled manner. Associating specific damage events with a force during a drop-weight impact test is often difficult due to the oscillations in the force history. In addition, a specific sequence of damage events may be identified during quasi-static loading while the final damage state is only identifiable after a drop-weight impact test. 5.2.2 To provide an estimate of the impact energy required to obtain a similar damage state for drop-weight impact testing if all others parameters are held constant. 5.2.3 To establish quantitatively the effects of stacking sequence, fiber surface treatment, variations in fiber volume fraction, and processing and environmental variables on the damage resistance of a particular composite laminate to a concentrated indentation force. 5.2.4 To compare quantitatively the relative values of the damage resistance parameters for composite materials with different constituents. The damage response parameters can include dent depth, damage dimensions and through-thickness locations, F max , E a , and E max , as well as the force versus indenter displacement curve. 5.2.5 To impart damage in a specimen for subsequent damage tolerance tests, such as Test Method D7137/D7137M . 5.2.6 To measure the indentation response of the specimen with and without bending using the two specimen configurations (edge supported and rigidly backed). 5.3 The properties obtained using this test method can provide guidance in regard to the anticipated damage resistance capability of composite structures of similar material, thickness, stacking sequence, etc. However, it must be understood that the damage resistance of a composite structure is highly dependent upon several factors including geometry, thickness, stiffness, mass, support conditions, etc. Significant differences in the relationships between force/energy and the resultant damage state can result due to differences in these parameters. For example, properties obtained using the specimen supported over a circular hole would more likely reflect the damage resistance characteristics of an un-stiffened monolithic skin or web than that of a skin attached to sub-structure which resists out-of-plane deformation. Similarly, test specimen properties would be expected to be similar to those of a panel with equivalent length and width dimensions, in comparison to those of a panel significantly larger than the test specimen, which tends to divert a greater proportion of the energy into elastic deformation. 5.4 The standard indenter geometry has a blunt, hemispherical tip. Historically, for the standard laminate configuration, this indenter geometry has generated a larger amount of internal damage for a given amount of external damage than is typically observed for similar indenters using sharp tips. Alternative indenter geometries may be appropriate depending upon the damage resistance characteristics being examined. For example, the use of sharp tip geometries may be appropriate for certain damage visibility and penetration resistance assessments. 5.5 Some testing organizations may desire to use this test method in conjunction with Test Method D7137/D7137M to assess the compression residual strength of specimens containing a specific damage state, such as a defined dent depth, damage geometry, etc. In this case, the testing organization should subject several specimens to multiple energy or force levels using this test method. A relationship between energy or force and the desired damage parameter can then be developed. Subsequent QSI and compression residual strength tests can then be performed using specimens indented at an interpolated energy or force level that is expected to produce the desired damage state.