1.1 本规程涵盖了使用硫酸铜溶液在通过铸造、拉拔、压制或其他成型方法制成形状后涂覆的铁或钢制品上的锌涂层（热浸镀锌、电镀或喷涂）中定位最薄点的程序。 1.2 单位- 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 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====== 2.1 本规程提供了在新涂层项目上定位锌涂层最薄部分的程序（参见 附录X1 )按照采购订单或合同中买方指定的ASTM委员会A05及其子委员会管辖下的产品规范生产。 2.2 实践的局限性: 2.2.1 使用通过不同工艺（如热浸镀锌、电镀或喷涂）沉积的锌涂层时，需要谨慎解释，因为不同的锌涂层系统之间的终点可能会有很大差异。 2.2.2 涂层厚度的变化可能是由于应用锌的过程或涂层零件的几何形状造成的。在热浸镀锌过程中，涂层厚度受熔融锌的排水模式的影响，而在锌喷涂（金属化）过程中，涂层厚度可能取决于操作员对喷嘴的操作。 零件的几何形状也会影响涂层厚度，尤其是在热浸镀锌过程中，零件上的峰谷会导致熔融锌积聚或变薄。 2.2.3 本规程不包括热浸或电泳涂装生产线的钢板，因为钢板产品通常在涂层工艺后进行额外成型。此外，在成型之前或之后连续或批量涂覆的所有镀锌电线和电线产品也不包括在本规程中。 小心 -过去的研究（始于1963年左右）表明，这种做法可能会受到操作员技术的影响。变化可能是由于用于擦拭样品的手压差或操作员无法识别终点。 2.2.4 该技术去除被检查零件表面的锌涂层。这种涂层去除使零件或物品在测试后无法使用。这种技术可能不适用于制造成最终配置的零件，因为它们在测试后是不可接受的。 2.2.5 本规程的结果不应用于预测镀锌层的使用寿命。其他因素，如最薄点的位置、使用中零件的方向和特定环境条件也会影响使用寿命。 2.3 可测试的涂层物品示例有:电气金属管和刚性导管、铸件和锻件以及结构钢； 在特殊硬件上，如杆线、建筑工人和农具硬件；螺栓、螺母、螺钉和其他通用五金件。

1.1 This practice covers the procedure for locating, by the use of a solution of copper sulfate, the thinnest spot in a zinc coating (hot dipped, electroplated, or sprayed) on iron or steel articles that are coated after the shape is produced by casting, drawing, pressing, or other forming methods. 1.2 Units— The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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 ====== 2.1 This practice provides the procedure to locate the thinnest portions of the zinc coating on newly coated items (see Appendix X1 ) produced to a product specification under the jurisdiction of ASTM Committee A05 and its subcommittees as designated by a purchaser in a purchase order or contract. 2.2 Limitations of the Practice: 2.2.1 The use of this practice with zinc coating deposited through different processes (such as hot dipped, electroplated, or sprayed) requires caution in interpretation since the end point may vary considerably between different zinc-coating systems. 2.2.2 Variations in coating thickness can be due to the process by which the zinc is applied or by the geometry of the part that is coated. During hot-dip galvanizing, the coating thickness is affected by the drainage pattern of the molten zinc, while during zinc spraying (metallizing), coating thickness can be dependent on the operator's manipulation of the spray nozzle. The geometry of the part can also influence coating thickness especially during hot-dip galvanizing, where peaks and valleys on the part can cause molten zinc to build up or thin out. 2.2.3 Excluded from this practice is sheet steel from hot-dip or electrocoating lines as the sheet products are normally subject to additional forming after the coating process. Also excluded from this practice are all zinc-coated wire and wire products either continuously or batch coated before or after forming. Caution —Past research (dating from around 1963) has indicated that this practice can be influenced by operator technique. Variations can be due to the difference in hand pressure used to wipe the sample or the inability of the operator to recognize the end point. 2.2.4 This technique removes the zinc coating on the surface of the part being examined. This coating removal makes the part or article unusable after testing. This technique may not be suitable for parts fabricated into their final configuration, since they will not be acceptable after testing. 2.2.5 The results of this practice should not be used to predict the service life of the galvanized coating. Other factors such as location of the thinnest spot, orientation of the part in service, and specific environmental conditions will also affect the service life. 2.3 Examples of coated articles that can be tested are: electrical metallic tubing and rigid conduit pipe, castings and forgings, and structural steel; on special hardware, such as pole line, builder's, and farm implement hardware; bolts, nuts, screws, and other miscellaneous general hardware.