批量热浸镀锌工艺机理的研究现状

Research Status of the Process Mechanism of Batch Hot-dip Galvanizing

热浸镀锌是钢铁材料户外长效防护的最佳选择。传统的调整参数、试加合金等"试错法"难以满足现代制造业的发展,故全面、完整的热浸镀锌机理研究已迫在眉睫。针对我国批量热浸镀锌产量大、重经验轻理论、技术落后、污染严重等特点,从镀层的形成机理、镀层的合金化机理、锌浴液态特征等方面综述分析了批量热浸镀锌工艺理论的研究现状和不足,指出了基体和锌浴界面之间的相互作用、合金元素添加的可预测性、浸镀后表面粘附锌液层的结晶、锌浴液态特征等研究的重要性。建议从以下几个方面完善热浸镀锌机理:加强基材离开锌浴至冷却结晶结束这一阶段镀层组织结构的演变研究;在研究镀层合金化机理的同时,注重合金化镀层的应用推广,尤其是加强低合金高强钢的热浸镀锌研究;重视并加强锌浴表面张力、流动性、结晶特性的液态特征研究和数据积累;在形层机理研究的基础上,结合工艺参数进行镀层的预设计及镀层预控制研究。

Hot dip galvanizing is the best method for outdoor long-term protection of steel materials. The traditional pa- rameters adjustment and tentatively adding alloy are difficult to meet the requirement of development of modem manufacturing, so comprehensive study of mechanism in hot dip galvanizing is imminent. In view of the large output of hot-dip galvanized steels, the emphasis on the experience and ignoring the theory, the outdated techniques and the serious pollution, the research status and deficiencies of the process theory of batch hot-dip galvanizing in China were comprehensively analyzed based on the coating formation mechanism, the mechanism of alloying coating, and zinc bath liquid characteristics. At the same time, it was pointed out that the interfacial reaction between the matrix and the zinc melt, the adding predictability of zinc alloy elements, the crystallization of zinc on the surface of the workpiece after withdrawing from zinc bath, are very important in the study on me- chanism of hot dip galvanizing. It was recommended to improve the mechanism of hot-dip galvanized from the following as- pects： the development of the microstructure of zinc coating from the workpiece leaving from zinc bath to the crystallizationending of zinc on the surface of the coating, the application of alloying coating is more important than the mechanism study of alloying coating, to strengthen the research of high-strength low-alloy steel in hot dip galvanizing, to strengthen the research and data accumulation of the surface tension, fluidity and crystallization characteristics of the zinc bath, to study on the pre-design and pre-control of the coating with the combination of the mechanism and the galvanizing parameters.