1.1 本试验方法描述了一种稳态技术，用于测定均匀不透明固体的导热系数λ（见 注释1和 2. ). 本试验方法适用于有效导热系数在0.2<λ<200 W范围内的材料/( m ·K） 在90 K和1300 K之间的温度范围内。它可以在这些范围外使用，但精度会降低。 注1: 就这项技术而言，如果试样的表观导热系数λ A. ，随厚度或横截面积的变化不超过±5 %. 对于由板或粘合在一起的板组成的复合材料或异质系统，试样应分别大于20个单位宽和20个单位厚，其中一个单位是最厚的板或板的厚度，因此一半单位的直径或长度变化将影响表观λ A. 小于±5 %. 对于在红外中不透明或部分透明的系统，由不均匀性和光子传输引起的组合误差应小于±5 %. 对高透明固体的测量必须附带红外吸收系数信息，或者必须将结果报告为表观导热系数λ A. . 注2: 该试验方法也可用于评估材料和复合材料的接触热导率/电阻。 1.2 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 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====== 5.1 导热系数的比较测量方法特别适用于工程材料，包括陶瓷、聚合物、金属和合金、耐火材料、碳和石墨，包括每种材料的组合和其他复合形式。 5.2 防护纵向系统的正确设计是困难的，在这种类型的方法中，试图建立结构和程序的细节，以涵盖可能给不具备热流理论、温度测量和一般测试实践相关技术知识的人带来困难的所有意外情况，是不实际的。 本试验方法的标准化无意以任何方式限制研究人员对新方法或改进程序的未来发展。然而，必须彻底测试新的或改进的技术。第节概述了仪器的鉴定要求 10 .

1.1 This test method describes a steady state technique for the determination of the thermal conductivity, λ, of homogeneous-opaque solids (see Notes 1 and 2 ). This test method is applicable to materials with effective thermal conductivities in the range 0.2 < λ < 200 W/( m ·K) over the temperature range between 90 K and 1300 K. It can be used outside these ranges with decreased accuracy. Note 1: For purposes of this technique, a system is homogeneous if the apparent thermal conductivity of the specimen, λ A , does not vary with changes of thickness or cross-sectional area by more than ±5 %. For composites or heterogeneous systems consisting of slabs or plates bonded together, the specimen should be more than 20 units wide and 20 units thick, respectively, where a unit is the thickness of the thickest slab or plate, so that diameter or length changes of one-half unit will affect the apparent λ A by less than ±5 %. For systems that are non-opaque or partially transparent in the infrared, the combined error due to inhomogeneity and photon transmission should be less than ±5 %. Measurements on highly transparent solids must be accompanied with infrared absorption coefficient information, or the results must be reported as apparent thermal conductivity, λ A . Note 2: This test method may also be used to evaluate the contact thermal conductance/resistance of materials and composites. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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 The comparative method of measurement of thermal conductivity is especially useful for engineering materials including ceramics, polymers, metals and alloys, refractories, carbons, and graphites including combinations and other composite forms of each. 5.2 Proper design of a guarded-longitudinal system is difficult and it is not practical in a method of this type to try to establish details of construction and procedures to cover all contingencies that might offer difficulties to a person without technical knowledge concerning theory of heat flow, temperature measurements, and general testing practices. Standardization of this test method is not intended to restrict in any way the future development by research workers of new or methods or improved procedures. However, new or improved techniques must be thoroughly tested. Requirements for qualifying an apparatus are outlined in Section 10 .