1.1 本规程涵盖了测量石墨材料性能的试验方法的应用和局限性。这些特性可用于气冷反应堆部件的设计和评估。 1.2 本文引用的试验方法适用于第节中定义的用于可更换和永久性部件的材料 7. 包括燃料元件；可拆卸反射元件和块；永久性侧反射器元件和块；堆芯支撑座和元件；控制棒、备用停机和可燃毒物压实；中子屏蔽材料。讨论了辐照材料测试的具体方面。 1.3 本规程包括从ASTM标准和指南中选择的测试方法，这些标准和指南专门用于测试中列出的材料 1.2 . 第节给出了对石墨组件的单独测试方法的评论 8. . 试验方法总结见 表1 . 1.4 以国际单位制表示的数值应视为标准值。国际单位制后括号中给出的值仅供参考，不被视为标准值。 1.5 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。 1.6 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====== 4.1 使用本文确定的推荐试验方法获得的性能数据可用于与使用石墨的核反应堆相关的研发、设计、制造控制、规范、性能评估和法规。 4.2 参考试验方法主要适用于未辐照和未氧化状态的试样。测试辐照试样通常需要不符合标准要求的试样几何形状。有关测试不合格几何形状的具体说明或建议，请参阅STP 1578 4. 和/或指南 D7775 . 在高温下测试辐照试样时，应考虑退火的影响（见 注1 ). 注1: 暴露于快中子辐射将导致石墨的原子和微观结构变化。当高能粒子（如快中子）撞击晶格并将碳原子从其平衡位置置换，从而产生晶格空位和间隙碳原子时，就会发生这种辐射损伤。位移损伤引起的晶格应变会导致石墨的结构和性能发生显著变化，并且是辐照温度和剂量的函数。 当石墨的温度高于辐照温度时，就会提供足够的能量，使石墨的结构退火回其原始状态。因此，使试样温度高于辐照温度的测量技术可能会导致性能值在测量过程中发生变化。因此，在低于辐照温度的辐照试样上进行的测量将产生代表辐照损伤的结果。然而，在高于辐照温度的温度下进行的测量可能包括退火的影响。 4.3 其他测试方法正在准备中，将纳入其中。提醒用户使用最新版本。

1.1 This practice covers the application and limitations of test methods for measuring the properties of graphite materials. These properties may be used for the design and evaluation of gas-cooled reactor components. 1.2 The test methods referenced herein are applicable to materials used for replaceable and permanent components as defined in Section 7 and includes fuel elements; removable reflector elements and blocks; permanent side reflector elements and blocks; core support pedestals and elements; control rod, reserve shutdown, and burnable poison compacts; and neutron shield material. Specific aspects with respect to testing of irradiated materials are addressed. 1.3 This practice includes test methods that have been selected from ASTM standards and guides that are specific to the testing of materials listed in 1.2 . Comments on individual test methods for graphite components are given in Section 8 . The test methods are summarized in Table 1 . 1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard. 1.5 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. 1.6 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 ====== 4.1 Property data obtained with the recommended test methods identified herein may be used for research and development, design, manufacturing control, specifications, performance evaluation, and regulatory statutes pertaining to nuclear reactors that utilize graphite. 4.2 The referenced test methods are applicable primarily to specimens in the non-irradiated and non-oxidized state. Testing irradiated specimens often requires specimen geometries that do not meet the requirements of the standard. Specific instructions or recommendations with respect to testing non-conforming geometries can be found in STP 1578 4 and/or Guide D7775 . When testing irradiated specimens at elevated temperatures, the effects of annealing should be considered (see Note 1 ). Note 1: Exposure to fast neutron radiation will result in atomic and microstructural changes to graphite. This radiation damage occurs when energetic particles, such as fast neutrons, impinge on the crystal lattice and displace carbon atoms from their equilibrium positions, creating a lattice vacancy and an interstitial carbon atom. The lattice strain that results from displacement damage causes significant structural and property changes in the graphite and is a function of the irradiation temperature and dose. When the temperature of the graphite is brought above the temperature at which it was irradiated, enough energy is provided that the structure of the graphite will anneal back to its original condition. Therefore, measurement techniques that bring the specimen temperature above the irradiation temperature can result in property values that change during the measurement process. For this reason, measurements made on irradiated test specimens below the irradiation temperature will produce results that are representative of the irradiation damage. However, measurements made at temperatures above the irradiation temperature could include the effects of annealing. 4.3 Additional test methods are in preparation and will be incorporated. The user is cautioned to employ the latest revision.