1.1 本试验方法涵盖了176°F（80°C）以下沥青软化点的测定。软化点较高的沥青应按试验方法进行试验 D2319 或测试方法 D3104 . 1.2 以英寸-磅单位表示的值应被视为标准值。括号中给出的值是对SI单位的数学转换，仅供参考，不被视为标准。 1.3 本标准并不旨在解决与其使用相关的所有安全性问题（如果有）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践并确定法规限制的适用性。 1.4 本国际标准是根据世界贸易组织Tec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的标准化原则制定的贸易壁垒委员会。 ======意义和用途====== 5.1 沥青在加热时不会发生固液相变，因此不具有真正的熔点。随着温度升高，沥青软化并变得不那么粘稠。软化点是任意定义的，应通过严格控制的方法确定，如果试验结果是可重复的，应仔细遵循该方法。 5.2 该测试可用于确定沥青的一致性，作为建立运输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 below 176 °F (80 °C). Pitches of higher softening point should be tested by Test Method D2319 or Test Method D3104 . 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that 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 ====== 5.1 Pitch does not go through a solid-liquid phase change when heated, and therefore it does not have a true melting point. As the temperature rises, pitch softens and becomes less viscous. The softening point is arbitrarily defined and shall be established by a closely controlled method which shall be carefully followed if test results are to be reproducible. 5.2 This test is useful in determining the consistency of pitch as one element in establishing the uniformity of shipments or sources of supply.