1.1 本指南介绍了使用现场试验测量镍和不锈钢上电沉积铬涂层厚度的方法，精度约为±20 % （章节 9 )。适用于厚度不超过1.2μm的情况。 2. 注1: 尽管该测试可用于厚度高达1.2μm的涂层，但有证据表明，在厚度大于0.5μm时，通过该方法获得的结果很高。 3. 此外，对于厚度超过0.5μm的涂层，建议使用两滴酸液，以防止在测试完成前耗尽测试溶液。 1.2 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。 1.3 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====== 4.1 装饰性铬涂层的厚度通常对其性能至关重要。 4.2 当不需要尽可能高的精度时，此程序可用于近似确定。为了进行更可靠的测定，可采用以下方法:方法 B504 ， B568 和 B588 。 4.3 本试验假设在规定条件下，盐酸对铬的溶解速率始终相同。

1.1 This guide covers the use of the spot test for the measurement of thicknesses of electrodeposited chromium coatings over nickel and stainless steel with an accuracy of about ±20 % (Section 9 ). It is applicable to thicknesses up to 1.2 μm. 2 Note 1: Although this test can be used for coating thicknesses up to 1.2 μm, there is evidence that the results obtained by this method are high at thicknesses greater than 0.5 μm. 3 In addition, for coating thicknesses above 0.5 μm, it is advisable to use a double drop of acid to prevent depletion of the test solution before completion of the test. 1.2 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. 1.3 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 ====== 4.1 The thickness of a decorative chromium coating is often critical to its performance. 4.2 This procedure is useful for an approximate determination when the best possible accuracy is not required. For more reliable determinations, the following methods are available: Methods B504 , B568 , and B588 . 4.3 This test assumes that the rate of dissolution of the chromium by the hydrochloric acid under the specified conditions is always the same.