1.1 本规范涵盖了铁、钢、铜和铜合金制品上电沉积锡铅涂层的要求，以保护其免受腐蚀( 注1 )，以改善和保持长时间存储的可焊性，并改善抗磨损特性。 注1: 锡铅涂层在室外暴露时可能会发生一些腐蚀。在正常的室内暴露中，锡铅对铁、铜和铜合金具有保护作用。涂层中的不连续处（凹坑或孔隙）可能会发生腐蚀。孔隙度随着厚度的增加而减少。锡铅涂层（焊料）的主要用途是作为可焊涂层和蚀刻掩模材料用于印刷电路行业。 1.2 本规范适用于含有至少50 % 最多70 % 锡本规范适用于mat、bright和flow- 光亮锡铅涂层。 注2: 锡铅电镀槽由氟硼酸锡和铅以及添加剂组成，以提高稳定性。添加专利增白剂可能会影响最终外观。没有光亮剂，涂层是无光泽的；使用增白剂，它们是半亮或明亮的。通过将毡涂层加热到锡铅熔点以上几秒钟，然后淬火，获得流动光亮涂层；棕榈油、氢化油或脂肪在260±10℃下用作传热介质 °C（500±20 °F），但也使用其他加热方法。流动增白的最大厚度约为7.5μm（0.3密耳）；较厚的涂层往往回流不均匀。零件的形状也是一个因素；平面回流比金属丝或圆形回流更不均匀( 附注3 ). 注3: 锡铅涂层中的挥发性杂质会在流动过程中引起起泡- 增亮导致空洞和粗糙。杂质可能来自镀液添加剂以及不当的冲洗和处理。 1.3 本规范不适用于未经加工的板材、带材或线材，也不适用于基本大径小于等于19的螺纹制品 毫米（0.75 英寸）。 1.4 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。 1.5 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《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。

1.1 This specification covers the requirements for electrodeposited tin-lead coatings on fabricated articles of iron, steel, copper, and copper alloys, to protect them against corrosion ( Note 1 ), to improve and preserve solderability over long periods of storage, and to improve anti-galling characteristics. Note 1: Some corrosion of tin-lead coatings may be expected in outdoor exposure. In normal indoor exposure, tin-lead is protective on iron, copper, and copper alloys. Corrosion may be expected at discontinuities (pits or pores) in the coating. Porosity decreases as the thickness is increased. A primary use of the tin-lead coating (solder) is with the printed circuit industry as a solderable coating and as an etch mask material. 1.2 This specification applies to electrodeposited coatings containing a minimum of 50 % and a maximum of 70 % tin. The specification applies to mat, bright, and flow-brightened tin-lead coatings. Note 2: Tin-lead plating baths are composed of tin and lead fluoborates and of addition agents to promote stability. The final appearance may be influenced by the addition of proprietary brighteners. Without brighteners, the coatings are mat; with brighteners, they are semibright or bright. Flow-brightened coatings are obtained by heating mat coatings to above the melting point of tin-lead for a few seconds and then quenching; palm oil, hydrogenated oils, or fats are used as a heat-transfer medium at a temperature of 260 ± 10 °C (500 ± 20 °F), but other methods of heating are also in use. The maximum thickness for flow-brightening is about 7.5 μm (0.3 mil); thicker coatings tend to reflow unevenly. The shape of the part is also a factor; flat surfaces tend to reflow more unevenly than wires or rounded shapes ( Note 3 ). Note 3: Volatile impurities in tin-lead coatings will cause bubbling and foaming during flow-brightening resulting in voids and roughness. The impurities can arise from plating solution addition agents and from improper rinsing and processing. 1.3 This specification does not apply to sheet, strip, or wire in the unfabricated form or to threaded articles having basic major diameters up to and including 19 mm (0.75 in.). 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.