ASTM E8∕E8M-21 Standard Test Methods for Tension Testing of Metallic Materials

1.1 这些试验方法包括在室温下对任何形式的金属材料进行拉伸试验，特别是测定屈服强度、屈服点伸长率、抗拉强度、伸长率和面积收缩率的方法。
1.2 大多数圆形试样的标距长度要求为4D E8 和5D E8M . 标距长度是两者之间最显著的差异 E8 和 E8M 试样。由粉末冶金（P/M）材料制成的试样可通过行业协议免除该要求，以将材料压制至特定投影面积和密度。
1.3 可能需要在特定材料的单独规范或试验方法中对这些试验方法的规定进行例外。有关示例，请参阅测试方法和定义 A370型 和试验方法 B557 和 B557M .
1.4 除非另有规定，否则室温应视为10至38°C[50至100°F]。
1.5 以国际单位制表示的数值应视为与英寸/磅单位分开。每个系统中规定的值不是精确的等价物；因此，每个系统必须相互独立使用。将两个系统的值合并可能会导致不符合标准。
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。
1.7 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 拉伸试验提供了材料在单轴拉伸应力下的强度和延展性信息。在某些情况下，这些信息可能有助于材料比较、合金开发、质量控制和设计。
4.2 从零件或材料的选定部分加工成标准尺寸的试样的拉伸试验结果可能并不完全代表整个最终产品的强度和延展性或其在不同环境中的使用行为。
4.3 这些测试方法被认为是商业装运验收测试的满意方法。 为此，测试方法已在行业中广泛使用。

1.1 These test methods cover the tension testing of metallic materials in any form at room temperature, specifically, the methods of determination of yield strength, yield point elongation, tensile strength, elongation, and reduction of area.
1.2 The gauge lengths for most round specimens are required to be 4D for E8 and 5D for E8M . The gauge length is the most significant difference between E8 and E8M test specimens. Test specimens made from powder metallurgy (P/M) materials are exempt from this requirement by industry-wide agreement to keep the pressing of the material to a specific projected area and density.
1.3 Exceptions to the provisions of these test methods may need to be made in individual specifications or test methods for a particular material. For examples, see Test Methods and Definitions A370 and Test Methods B557 , and B557M .
1.4 Room temperature shall be considered to be 10 to 38°C [50 to 100°F] unless otherwise specified.
1.5 The values stated in SI units are to be regarded as separate from inch/pound units. The values stated in each system are not exact equivalents; therefore each system must be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.
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 ======
4.1 Tension tests provide information on the strength and ductility of materials under uniaxial tensile stresses. This information may be useful in comparisons of materials, alloy development, quality control, and design under certain circumstances.
4.2 The results of tension tests of specimens machined to standardized dimensions from selected portions of a part or material may not totally represent the strength and ductility properties of the entire end product or its in-service behavior in different environments.
4.3 These test methods are considered satisfactory for acceptance testing of commercial shipments. The test methods have been used extensively in the trade for this purpose.