1.1 本试验方法包括通过本试验方法测定软化点在50°C至180°C范围内的沥青的软化点，并给出与通过试验方法获得的结果相当的结果 D2319 80以上 °C（176°F）。 1.2 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。 1.3 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。 1.4 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 沥青在加热时不会发生固液相变，因此没有真正的熔点。随着温度升高，沥青逐渐软化或变得不那么粘稠。因此，如果要使试验值可再现，则必须通过任意但严格定义的方法确定软化点。 4.2 该测试方法有助于确定沥青的一致性，作为确定装运或供应来源一致性的一个要素。

1.1 This test method covers the determination of the softening point of pitches having softening points in the range from 50 °C to 180 °C by this test method, and gives results comparable to those obtained by Test Method D2319 above 80 °C (176 °F). 1.2 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. 1.3 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. 1.4 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 Pitch does not go through a solid-liquid phase change when heated, and therefore does not have a true melting point. As the temperature is raised pitch gradually softens or becomes less viscous. For this reason, the determination of the softening point must be made by an arbitrary, but closely defined, method if the test values are to be reproducible. 4.2 This test method is useful in determining the consistency of pitches as one element in establishing the uniformity of shipments or sources of supply.