T/CSEA 10-2019 Metal coating zinc-iron alloy electroplating layer on steel
T/CSEA 10-2019 Metal coating zinc-iron alloy electroplating layer on steel
Basic Information
Scope
Scope: This standard specifies the technical requirements and test methods for zinc-iron alloy coatings with an iron content of 0.2% to 1.0% (by mass). This standard applies to zinc-iron alloy electroplating coatings on steel. Other base metals can be used as reference. Main technical content: 7. Coating requirements 7.1 Appearance 7.1.1 Surface color, characteristics, and condition of the coating 7.1.2 Surface defects of the coating 7.2 Coating thickness On the main surface, all parts that can be contacted by a 20-mm diameter ball shall meet the minimum local thickness values specified in the grading table (Table 1). If required by the purchaser, other parts of the main surface shall also meet the minimum local thickness requirements. Note: The coating thickness of threaded parts is limited by the thread grade and fit dimensions. GB 5267.1 specifies the maximum coating thickness for standard threads. 7.3 Adhesion strength The coating and base material shall be firmly bonded, without peeling, bubbling, or detachment. 7.4 Corrosion resistance Within the specified time and cycle, and under continuous spraying for not less than the required duration, the main surface of the coating shall have no white, gray-black, or black corrosion products; or no corrosion on the base material; or meet the specified protection grade according to the test cycle specified in the product drawings and rated according to GB/T 6461. 7.5 Coating composition The coating contains 0.2% to 1.0% iron (by mass), with the remainder being zinc. 7.6 Application of conversion films Conversion films, especially chromate conversion films, can improve the corrosion resistance of zinc-iron alloy coatings. Only when explicitly required by the purchaser can the chromate conversion film be omitted or replaced with other conversion films. For details on the types of conversion films that can be formed on zinc-iron alloy electroplating coatings, see GB/T 9800. The conversion fi