钢丝热镀锌-10铝-混合稀土合金镀层工艺

摘要

A process for hot-dip galvanizing Zn-10%Al-mixed rare earth alloy coating on steel wires based on the principle of electrodeposition (i.e. electroplating a Zn coating prior to galvanizing) was developed as a substitute to common double-dip galvanizing method. The bath composition and operation conditions of individual procedure were presented. It is stressed that the pretreatment of steel wire is the key point. Electrolytic degreasing twice, quartz sand rubbing, and overflow rinsing are employed to produce clean steel wire surface and ensure the quality of coating. The temperature range of molten alloy (455-460 °C) and other technical key points such as the nitrogen wiping temperature were given. The process has advantages of energy saving and low cost as compared with the double-dip method. The causes for the formation of floating aluminum-rich product which influences the coating quality and its treatment method for making the coating smooth and free of defects such as lumps and bumps were discussed. The surface quality of steel wires obtained by the process is stable, and the technical and physicochemical indexes meet the requirements of the standard YB/T 4221-2010 Coated Steel Wire for Machine Woven Steel Wire Mesh.%利用电沉积原理，提出了一种在钢丝表面热浸镀锌-10%铝-稀土合金镀层的工艺，在热浸镀合金之前电沉积一层锌镀层，以代替普通的“双镀法”。给出了各工序的溶液配方及工艺条件。指出重点应放在钢丝的预处理上。采用2道电解脱脂以及石英砂擦拭、水溢流漂洗工艺，得到非常清洁的钢丝表面，才能保证镀层质量。给出了合金液温度范围(455~460°C)、氮气抹拭温度参数等技术要点。该工艺较“双镀法”节约能源，生产成本低。探讨了影响镀层质量的富集铝漂浮物的产生原因及处理办法，使镀层光滑，无“疙瘩”等缺陷。该工艺所得钢丝的表面质量稳定，各项理化技术指标达到YB/T 4221-2010《机编钢丝网用镀层钢丝》标准的要求。