1.1 本试验方法包括使用X射线光谱法测定金属和一些非金属涂层的厚度。 1.2 给定涂层的最大可测量厚度是指超过该厚度时，来自涂层或基材的特征二次X辐射强度对厚度的微小变化不再敏感。 1.3 本试验方法测量单位面积的涂层质量，也可以用线性厚度单位表示，前提是涂层密度已知。 1.4 本试验方法不包括X射线管中产生的辐射或放射性同位素源发出的辐射的人员防护问题。关于这一重要方面的信息，应参考国家辐射防护和测量委员会、联邦公报、核管理委员会、国家标准和技术研究所（原国家标准局）的最新文件，以及州和地方规范（如有）。 1.5 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。 1.6 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 这是一种灵敏、非接触和无损的方法，用于测量金属和一些非金属涂层的涂层厚度（在某些情况下，涂层成分），厚度范围从0.01μm到75μm，具体取决于涂层和基材。 它可用于测量其他技术无法测量的涂层和基底组合。 5.2 涂层厚度是在役涂层性能的一个重要因素。

1.1 This test method covers the use of X-ray spectrometry to determine thickness of metallic and some nonmetallic coatings. 1.2 The maximum measurable thickness for a given coating is that thickness beyond which the intensity of the characteristic secondary X radiation from the coating or the substrate is no longer sensitive to small changes in thickness. 1.3 This test method measures the mass of coating per unit area, which can also be expressed in units of linear thickness provided that the density of the coating is known. 1.4 Problems of personnel protection against radiation generated in an X-ray tube or emanating from a radioisotope source are not covered by this test method. For information on this important aspect, reference should be made to current documents of the National Committee on Radiation Protection and Measurement, Federal Register, Nuclear Regulatory Commission, National Institute of Standards and Technology (formerly the National Bureau of Standards), and to state and local codes if such exist. 1.5 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. 1.6 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 This is a sensitive, noncontact, and nondestructive method for measuring the coating thickness (and in some cases, coating composition) of metallic and some nonmetallic coatings over a range of thicknesses from as little as 0.01 μm to as much as 75 μm depending on the coating and substrate materials. It can be used to measure coating and base combinations that are not readily measured by other techniques. 5.2 The coating thickness is an important factor in the performance of a coating in service.