1.1 本试验方法 ( 1. , 2. , 3. , 4. , 5. ) 2. 涵盖在标准试样上以及在规定的制备和测试条件下测试时胶粘剂断裂强度的测定( 注1 ). 1.2 该测试方法很有用，因为它可以用于开发粘接组件的设计参数。 注1: 虽然本试验方法旨在用于金属对金属应用，但可用于测量使用塑料粘附物的粘合剂的断裂性能，前提是考虑了塑料粘附物的厚度和刚度。 1.3 以国际单位制表示的数值应视为标准。括号中给出的值仅供参考。 1.4 本标准并非旨在解决与其使用相关的所有安全问题（如有）。 本标准的用户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（TBT）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》中确立的国际公认标准化原则制定的。 ====意义和用途====== 注2: 粘接试样中的裂纹扩展可以通过两种方式进行:( 1. )通过缓慢稳定扩展，其中裂纹速度由十字头速率或( 2. )通过运行停止扩展，其中静止裂纹突然向前跳出十字头- 预测速率。第一类裂纹扩展表示为扁平；第二种类型由于出现自记记录而达到高峰。平坦行为是胶粘剂或试验温度的特征，或两者兼而有之，对于这些胶粘剂而言，起爆之间没有差异， G 1c ，并逮捕， G 1a . 例如，上述测试的橡胶改性薄膜粘合剂 −17.8°C（0°F）的所有样品均显示出平坦的自拍照记录。下面测试的所有改性材料均显示出峰值曲线−73°C(−100°F），通常用于未改性环氧树脂。 应注意的是，峰值和平坦行为均由与裂纹长度无关的试样确定。对于其他样本或结构 G 增加 一 在恒定载荷下，无论粘合剂特性如何，裂纹扩展的开始都会导致快速完全破裂。 5.1 财产 G 1c （和 G 1a 如果相关），则通过本试验方法确定材料在严重拉伸约束下存在尖锐裂纹的情况下，在中性环境中对缓慢稳定或停转破裂的阻力，从而使裂纹前缘附近的应力状态接近可拉伸平面应变，与约束方向上的裂纹尺寸和试样尺寸相比，裂纹尖端塑性区较小。尚未证明坚韧的粘合剂系统完全符合这一标准。因此，使用基于该假设的方程开发的数据可能不代表平面应变断裂值。脆性或韧性差异很大的粘合剂系统之间的断裂韧性比较应考虑到这一点。 一般来说，具有类似类型韧性的系统 ( 6. , 7. , 8. , 9 , 10 ) 可以比较环境对单个系统韧性的影响。A. G 1c 该值被认为代表由制造变量定义的给定温度、应变速率和粘合条件下的断裂韧性下限值。该值可用于估计在役材料的失效应力和缺陷尺寸之间的关系，其中预计会出现上述高约束条件。关于在线弹性断裂力学方面开发本试验方法的基础的背景信息，可在参考文献中找到 ( 4. ) 和 ( 8. ) . 5.1.1 循环荷载可导致裂纹扩展 G 1. 值小于 G 1c 价值此外，某些环境的存在可能会促进循环或持续载荷下的渐进稳定裂纹扩展。因此，应用 G 1c 在设计服务组件时，应意识到 G 由于缓慢的稳定裂纹扩展，服务中可能出现的先前裂纹增加。 5.2 本试验方法可用于以下目的: 5.2.1 在研究和开发中，从数量上确定胶粘剂成分、底漆、被粘物表面处理、支撑胶粘剂载体（scrim）、加工变量和环境影响对使用性能的重要影响。 5.2.2 在役评估，以确定粘合剂系统对特定应用的适用性，其中规定了应力条件，并且可以确定最大缺陷尺寸。 5.2.3 用于验收规范和制造质量控制，但只有在有可靠的基础来规范最低 G 1c 价值观规范 G 1c 与特定应用相关的值应表示已对部件进行了与预期载荷历史和环境相关的断裂控制研究，以及与使用前和预期寿命内后续应用的裂纹检测程序的灵敏度和可靠性相关的断裂控制研究。

1.1 This test method ( 1 , 2 , 3 , 4 , 5 ) 2 covers the determination of fracture strength in cleavage of adhesives when tested on standard specimens and under specified conditions of preparation and testing ( Note 1 ). 1.2 This test method is useful in that it can be used to develop design parameters for bonded assemblies. Note 1: While this test method is intended for use in metal-to-metal applications it may be used for measuring fracture properties of adhesives using plastic adherends, provided consideration is given to the thickness and rigidity of the plastic adherends. 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 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 ====== Note 2: Crack growth in adhesive bond specimens can proceed in two ways: ( 1 ) by a slow-stable extension where the crack velocity is dictated by the crosshead rate or ( 2 ) by a run-arrest extension where the stationary crack abruptly jumps ahead outrunning the crosshead-predicted rate. The first type of crack extension is denoted flat; the second type peaked because of the appearance of the autographic record. The flat behavior is characteristic of adhesives or test temperatures, or both, for these adhesives where there is no difference between initiation, G 1c , and arrest, G 1a . For example, the rubber modified film adhesives tested above −17.8°C (0°F) all exhibit flat autographic records. Peaked curves are exhibited for all modified materials tested below −73°C (−100°F) and in general for unmodified epoxies. It should be noted that both peaked and flat behaviors are determined from a crack-length-independent specimen. For other specimens or structures where G increases with a at constant load the onset of crack growth would result in rapid complete fracturing whatever the adhesive characteristics. 5.1 The property G 1c (and G 1a if relevant) determined by this test method characterizes the resistance of a material to slow-stable or run-arrest fracturing in a neutral environment in the presence of a sharp crack under severe tensile constraint, such that the state of stress near the crack front approaches tritensile plane strain, and the crack-tip plastic region is small compared with the crack size and specimen dimensions in the constraint direction. It has not been proven that tough adhesive systems fully meet this criteria. Therefore, data developed using equations based on this assumption may not represent plane-strain fracture values. Comparison of fracture toughness between adhesive systems widely different in brittleness or toughness should take this into consideration. In general, systems of similar type toughness ( 6 , 7 , 8 , 9 , 10 ) can be compared as can the effect of environment on toughness of a single system. A G 1c value is believed to represent a lower limiting value of fracture toughness for a given temperature, strain rate, and adhesive condition as defined by manufacturing variables. This value may be used to estimate the relation between failure stress and defect size for a material in service wherein the conditions of high constraint described above would be expected. Background information concerning the basis for development of this test method in terms of linear elastic fracture mechanics may be found in Refs ( 4 ) and ( 8 ) . 5.1.1 Cyclic loads can cause crack extension at G 1 values less than G 1c value. Furthermore, progressive stable crack extension under cyclic or sustained load may be promoted by the presence of certain environments. Therefore, application of G 1c in the design of service components should be made with awareness of the G increase for a prior crack which may occur in service due to slow-stable crack-extension. 5.2 This test method can serve the following purposes: 5.2.1 In research and development to establish, in quantitative terms, significant to service performance, the effects of adhesive composition, primers, adherend surface treatments, supporting adhesive carriers (scrim), processing variables, and environmental effects. 5.2.2 In service evaluation to establish the suitability of an adhesive system for a specific application for which the stress conditions are prescribed and for which maximum flaw sizes can be established with confidence. 5.2.3 For specifications of acceptance and manufacturing quality control, but only when there is a sound basis for specification of minimum G 1c values. The specification of G 1c values in relation to a particular application should signify that a fracture control study has been conducted on the component in relation to the expected history of loading and environment, and in relation to the sensitivity and reliability of the crack detection procedures that are to be applied prior to service and subsequently during the anticipated life.