【国外标准】 Standard Specification for Zinc-5 % Aluminum (Hot-Dip) Coatings on Iron and Steel Products

This specification covers the requirements for zinc-5% aluminium coated, by the hot-dip process on iron and steel products. The coating may also contain small amounts of elements other than zinc and aluminium that are intended to improve processing and the characteristics of the coated product. This specification also examines the coating properties of the material, such as coating thickness and finish. It also identifies the tests that are conducted on the material, namely the thickness of coating test, the magnetic thickness measurements, the stripping method, the weighing before and after hot-dip coating, microscopy, adhesion, and embrittlement.1.1 This specification covers the requirements for zinc-5 % aluminum coated, by the hot-dip process on iron and steel products. The coating may also contain small amounts of elements other than zinc and aluminum that are intended to improve processing and the characteristics of the coated product. These metallic coatings include zinc- 5 %-aluminum (Zn-5Al), zinc-5 %-aluminum-mischmetal (Zn-5Al-MM) and zinc-5 %-aluminum-magnesium (Zn- %Al-Mg).1.2 This specification covers both un-fabricated products and fabricated products, for example, assembled steel products, structural steel fabrications, large tubes already bent or welded before hot-dip coating, and wire work fabricated from uncoated steel wire. This specification, also, covers steel forgings and iron castings incorporated into pieces fabricated, before hot-dip coating or which are too large to be centrifuged (or otherwise handled to remove excess molten bath metal).1.3 Fabricated reinforcing steel bar assemblies are covered by the present specification.1.4 This specification is applicable to orders in either inch-pound units (as A1072) or SI units (as A1072M). Inch-pound units and SI units are not necessarily exact equivalents. Within the text of this specification and where appropriate, SI units are shown in parentheses. Each system shall be used independently of the other without combining values in any way. In the case of orders in SI units, all testing and inspection shall be done using the metric equivalent of the test or inspection method as appropriate. In the case of orders in SI units, such shall be stated to the hot-dip coater when the order is placed.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.