1.1 本规程提供了在不超过1200°F[650°C]的温度下使用电磁声换能器（EMAT）（一种非接触脉冲回波法）测量材料厚度的指南。 1.2 这种做法适用于任何导电或铁磁材料，或两者都适用，其中超声波将以恒定速度在整个零件上传播，并且可以从中获得和分辨背反射。 1.3 单位- 以国际单位制或英寸磅单位表示的数值应单独视为标准值。 每个系统中规定的值可能不完全相等；因此，每个系统应独立使用。将两个系统的值合并可能导致不符合标准。 1.4 本标准并不旨在解决与其使用相关的所有安全问题（如有）。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，并确定监管限制的适用性。 1.5 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《国际标准、指南和建议制定原则决定》中确立的国际公认标准化原则制定的。 =====意义和用途====== 5.1 所述方法提供了温度不超过1200°F[650°C]的材料截面厚度的间接测量。测量是从物体的一侧进行的，无需接近后表面。 5.2 超声波厚度测量广泛应用于许多材料的基本形状和产品、精密加工零件，并用于确定工艺设备中由腐蚀和侵蚀引起的壁减薄。 5.3 在引用的参考文献中可以找到确定特定应用的超声波测厚仪的性能和限制的建议( 1 , 2 ). 6

1.1 This practice provides guidelines for measuring the thickness of materials using Electromagnetic Acoustic Transducers (EMAT), a non-contact pulse-echo method, at temperatures not to exceed 1200°F [650°C]. 1.2 This practice is applicable to any electrically conductive or ferromagnetic material, or both, in which ultrasonic waves will propagate at a constant velocity throughout the part, and from which back reflections can be obtained and resolved. 1.3 Units— The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard. 1.4 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. 1.5 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 methods described provide indirect measurement of the thickness of sections of materials not exceeding temperatures of 1200°F [650°C]. Measurements are made from one side of the object, without requiring access to the rear surface. 5.2 Ultrasonic thickness measurements are used extensively on basic shapes and products of many materials, on precision machined parts, and to determine wall thinning in process equipment caused by corrosion and erosion. 5.3 Recommendations for determining the capabilities and limitations of ultrasonic thickness gages for specific applications can be found in the cited references ( 1 , 2 ). 6