1.1 这些试验方法包括在规定的环境条件下测定塑料的拉伸和压缩蠕变以及蠕变断裂（见 3.2 ). 1.2 在这些试验方法中，如试验方法中所述，采用三点加载 D790 ，用于测量弯曲蠕变。但是，使用中描述的设备和原理进行四点加载 D6272 也允许作为一种选择。 1.3 对于蠕变断裂的测量，拉伸是首选的应力模式，因为对于某些韧性塑料，在弯曲或压缩时不会发生断裂。 1.4 通过这些试验方法获得的试验数据是相关的，适用于工程设计。 1.5 以国际单位制表示的数值应视为标准。 括号中的值仅供参考。 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和健康实践，并确定监管限制的适用性。 中给出了具体的警告声明 6.8.2 . 注1: 本标准和ISO 899第1部分和第2部分涉及相同的主题，但技术内容不同（并且无法直接比较两种试验方法的结果）。国际标准化组织 899第1部分论述了拉伸蠕变和蠕变到断裂和ISO 899第2部分论述了弯曲蠕变。ISO中未提及压缩蠕变 899 ====意义和用途====== 5.1 蠕变和蠕变断裂试验的数据对于预测长期荷载下材料的蠕变模量和强度以及预测此类荷载可能导致的任何尺寸变化是必要的。 5.2 这些试验方法的数据适用于:( 1. )为了比较材料( 2. )在装配零件的设计中( 3. )表征塑料在恒定负载下的长期性能，以及( 4. )在某些条件下，出于规范目的。 5.3 在继续进行本试验方法之前，应参考被测材料的规范。材料规范中涵盖的任何试样制备、调节、尺寸和/或测试参数应优先于本测试方法中提及的参数，除非这样做会与进行测试的目的相冲突。 如果没有材料规范，则默认条件适用。

1.1 These test methods cover the determination of tensile and compressive creep and creep-rupture of plastics under specified environmental conditions (see 3.2 ). 1.2 In these test methods three-point loading, as described in Test Methods D790 , is used for measurement of creep in flexure. However, four-point loading using the equipment and principles described in D6272 is also permitted as an option. 1.3 For measurements of creep-rupture, tension is the preferred stress mode because for some ductile plastics rupture does not occur in flexure or compression. 1.4 Test data obtained by these test methods are relevant and appropriate for use in engineering design. 1.5 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only. 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 and health practices and determine the applicability of regulatory limitations prior to use. A specific warning statement is given in 6.8.2 . Note 1: This standard and ISO 899 Parts 1 and 2 address the same subject matter, but differ in technical content (and results cannot be directly compared between the two test methods). ISO 899 Part 1 addresses tensile creep and creep to rupture and ISO 899 Part 2 addresses flexural creep. Compressive creep is not addressed in ISO 899. ====== Significance And Use ====== 5.1 Data from creep and creep-rupture tests are necessary to predict the creep modulus and strength of materials under long-term loads and to predict any dimensional changes that will potentially occur as a result of such loads. 5.2 Data from these test methods are suitable for use: ( 1 ) to compare materials, ( 2 ) in the design of fabricated parts, ( 3 ) to characterize plastics for long-term performance under constant load, and ( 4 ) under certain conditions, for specification purposes. 5.3 Before proceeding with this test method, reference shall be made to the specification of the material being tested. Any specimen preparation, conditioning, dimensions, and/or testing parameters covered in the material specification shall take precedence over those mentioned in this test method, except in cases where to do so would conflict with the purpose for conducting testing. If there are no material specifications, then the default conditions apply.