1.1 本规程描述了应用于各种刚性基材的干涂层粉末的厚度测量。使用其中一些程序可能需要修复涂层粉末。本规程涵盖便携式仪器的使用。它旨在补充制造商的仪表操作说明，而不是取代它们。它包括关键术语的定义、参考文件、实践的意义和用途以及文书的优点和局限性。 1.2 提供了三种测量干涂层粉末厚度的程序: 1.2.1 程序A-- 使用刚性金属缺口（梳状）规。 1.2.2 程序B-- 使用磁性或涡流涂层测厚仪。 1.2.3 程序C-- 采用非接触式超声波粉末测厚仪。 1.3 涂层粉末通常在固化过程中厚度减小。因此，其中一些程序需要建立一个折减系数来预测粉末涂层的固化膜厚度。 1.4 程序A和程序B 测量在预固化、预胶凝状态下施加的涂层粉末的厚度（高度或深度）。通过将结果与在相同位置测得的固化粉末厚度进行比较，可以确定折减系数，并将其应用于相同涂层粉末的未来厚度测量。 1.5 程序C 导致基于典型涂层粉末的校准的固化状态的预测厚度值。 如果所讨论的粉末不是典型的，则可以进行调整，以使计量器读数与其他测量方法确定的实际固化值一致。 1.6 以国际单位制表示的数值应视为标准。括号中给出的值仅供参考。 1.7 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。 1.8 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 成品涂层的许多物理和外观性能都受到薄膜厚度的影响。薄膜厚度会影响涂层的颜色、光泽、表面轮廓、附着力、柔韧性、抗冲击性和硬度。当薄膜厚度不在公差范围内时，涂层后组装的零件的配合可能会受到影响。因此，涂层必须在一定的最小和最大膜厚度规格范围内涂覆，以优化其预期用途。 5.2 所有程序都包括测量预固化、预胶凝状态下的涂层粉末，以帮助确保正确的固化膜厚度。这使得应用系统能够在固化过程之前进行设置和微调。 反过来，这将减少废料和过度喷涂的数量。准确的预测有助于避免剥离和重新涂覆，这可能会导致附着力和涂层完整性问题。 5.3 固化粉末涂层厚度的测量可以根据基材使用不同的方法进行。可以使用磁性和涡流涂层厚度计对金属基底进行无损测量（见实施规程 D7091 ). 可以使用超声波涂层厚度计对非金属基底进行无损测量（见试验方法 D6132 ). 可以使用横截面仪器对刚性基底进行破坏性测量（见实践 D4138 ).

1.1 This practice describes the thickness measurement of dry coating powders applied to a variety of rigid substrates. Use of some of these procedures may require repair of the coating powder. This practice covers the use of portable instruments. It is intended to supplement the manufacturers’ instructions for their operation of the gauges and is not intended to replace them. It includes definitions of key terms, reference documents, the significance and use of the practice, and the advantages and limitations of the instruments. 1.2 Three procedures are provided for measuring dry coating powder thickness: 1.2.1 Procedure A— Using rigid metal notched (comb) gauges. 1.2.2 Procedure B— Using magnetic or eddy current coating thickness gauges. 1.2.3 Procedure C— Using non-contact ultrasonic powder thickness instruments. 1.3 Coating powders generally diminish in thickness during the curing process. Some of these procedures therefore require a reduction factor be established to predict cured film thickness of powder coatings. 1.4 Procedure A and Procedure B measure the thickness (height or depth) of the applied coating powders in the pre-cured, pre-gelled state. By comparing results to the measured cured powder thickness in the same location, a reduction factor can be determined and applied to future thickness measurements of the same coating powder. 1.5 Procedure C results in a predicted thickness value of the cured state based on a calibration for typical coating powders. If the powder in question is not typical then an adjustment can be made to align gauge readings with the actual cured values as determined by other measurement methods. 1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.7 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. 1.8 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 Many physical and appearance properties of the finished coating are affected by the film thickness. Film thickness can affect the color, gloss, surface profile, adhesion, flexibility, impact resistance and hardness of the coating. The fit of pieces assembled after coating can be affected when film thickness is not within tolerance. Therefore coatings must be applied within certain minimum and maximum film thickness specifications to optimize their intended use. 5.2 All procedures involve taking measurements of applied coating powders in the pre-cured, pre-gelled state to help insure correct cured film thickness. This enables the application system to be set up and fine-tuned prior to the curing process. In turn, this will reduce the amount of scrap and over-spray. Accurate predictions help avoid stripping and re-coating which can cause problems with adhesion and coating integrity. 5.3 Measurements of cured powder coating thickness can be made using different methods depending upon the substrate. Non-destructive measurements over metal substrates can be made with magnetic and eddy current coating thickness gauges (see Practice D7091 ). Non-destructive measurements over non-metal substrates can be made with ultrasonic coating thickness gauges (see Test Method D6132 ). Destructive measurements over rigid substrates can be made with cross-sectioning instruments (see Practices D4138 ).